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http://rosettacode.org/wiki/Sorting_algorithms/Insertion_sort | Sorting algorithms/Insertion sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
This page uses content from Wikipedia. The original article was at Insertion sort. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
An O(n2) sorting algorithm which moves elements one at a time into the correct position.
The algorithm consists of inserting one element at a time into the previously sorted part of the array, moving higher ranked elements up as necessary.
To start off, the first (or smallest, or any arbitrary) element of the unsorted array is considered to be the sorted part.
Although insertion sort is an O(n2) algorithm, its simplicity, low overhead, good locality of reference and efficiency make it a good choice in two cases:
small n,
as the final finishing-off algorithm for O(n logn) algorithms such as mergesort and quicksort.
The algorithm is as follows (from wikipedia):
function insertionSort(array A)
for i from 1 to length[A]-1 do
value := A[i]
j := i-1
while j >= 0 and A[j] > value do
A[j+1] := A[j]
j := j-1
done
A[j+1] = value
done
Writing the algorithm for integers will suffice.
| #Action.21 | Action! | PROC PrintArray(INT ARRAY a INT size)
INT i
Put('[)
FOR i=0 TO size-1
DO
IF i>0 THEN Put(' ) FI
PrintI(a(i))
OD
Put(']) PutE()
RETURN
PROC InsertionSort(INT ARRAY a INT size)
INT i,j,value
FOR i=1 TO size-1
DO
value=a(i)
j=i-1
WHILE j>=0 AND a(j)>value
DO
a(j+1)=a(j)
j==-1
OD
a(j+1)=value
OD
RETURN
PROC Test(INT ARRAY a INT size)
PrintE("Array before sort:")
PrintArray(a,size)
InsertionSort(a,size)
PrintE("Array after sort:")
PrintArray(a,size)
PutE()
RETURN
PROC Main()
INT ARRAY
a(10)=[1 4 65535 0 3 7 4 8 20 65530],
b(21)=[10 9 8 7 6 5 4 3 2 1 0
65535 65534 65533 65532 65531
65530 65529 65528 65527 65526],
c(8)=[101 102 103 104 105 106 107 108],
d(12)=[1 65535 1 65535 1 65535 1
65535 1 65535 1 65535]
Test(a,10)
Test(b,21)
Test(c,8)
Test(d,12)
RETURN |
http://rosettacode.org/wiki/Sorting_algorithms/Permutation_sort | Sorting algorithms/Permutation sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Implement a permutation sort, which proceeds by generating the possible permutations
of the input array/list until discovering the sorted one.
Pseudocode:
while not InOrder(list) do
nextPermutation(list)
done
| #Maple | Maple | arr := Array([17,0,-1,72,0]):
len := numelems(arr):
P := Iterator:-Permute(len):
for p in P do
lst:= convert(arr[sort(convert(p,list),output=permutation)],list):
if (ListTools:-Sorted(lst)) then
print(lst):
break:
end if:
end do: |
http://rosettacode.org/wiki/Sorting_algorithms/Permutation_sort | Sorting algorithms/Permutation sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Implement a permutation sort, which proceeds by generating the possible permutations
of the input array/list until discovering the sorted one.
Pseudocode:
while not InOrder(list) do
nextPermutation(list)
done
| #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | PermutationSort[x_List] := NestWhile[RandomSample, x, Not[OrderedQ[#]] &] |
http://rosettacode.org/wiki/Sorting_algorithms/Pancake_sort | Sorting algorithms/Pancake sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array of integers (of any convenient size) into ascending order using Pancake sorting.
In short, instead of individual elements being sorted, the only operation allowed is to "flip" one end of the list, like so:
Before: 6 7 8 9 2 5 3 4 1
After: 9 8 7 6 2 5 3 4 1
Only one end of the list can be flipped; this should be the low end, but the high end is okay if it's easier to code or works better, but it must be the same end for the entire solution. (The end flipped can't be arbitrarily changed.)
Show both the initial, unsorted list and the final sorted list.
(Intermediate steps during sorting are optional.)
Optimizations are optional (but recommended).
Related tasks
Number reversal game
Topswops
Also see
Wikipedia article: pancake sorting.
| #Eiffel | Eiffel |
class
PANCAKE_SORT [G -> COMPARABLE]
feature {NONE}
arraymax (array: ARRAY [G]; upper: INTEGER): INTEGER
--- Max item of 'array' between index 1 and 'upper'.
require
upper_index_positive: upper >= 0
array_not_void: array /= Void
local
i: INTEGER
cur_max: G
do
from
i := 1
cur_max := array.item (i)
Result := i
until
i + 1 > upper
loop
if array.item (i + 1) > cur_max then
cur_max := array.item (i + 1)
Result := i + 1
end
i := i + 1
end
ensure
Index_positive: Result > 0
end
reverse_array (ar: ARRAY [G]; upper: INTEGER): ARRAY [G]
-- Array reversed from index one to upper.
require
upper_positive: upper > 0
ar_not_void: ar /= Void
local
i, j: INTEGER
new_array: ARRAY [G]
do
create Result.make_empty
Result.deep_copy (ar)
from
i := 1
j := upper
until
i > j
loop
Result [i] := ar [j]
Result [j] := ar [i]
i := i + 1
j := j - 1
end
ensure
same_length: ar.count = Result.count
end
sort (ar: ARRAY [G]): ARRAY [G]
-- Sorted array in ascending order.
local
i: INTEGER
do
create Result.make_empty
Result.deep_copy (ar)
from
i := ar.count
until
i = 1
loop
Result := reverse_array (reverse_array (Result, arraymax (Result, i)), i)
i := i - 1
end
ensure
same_length: ar.count = Result.count
Result_sorted: is_sorted (Result)
end
is_sorted (ar: ARRAY [G]): BOOLEAN
--- Is 'ar' sorted in ascending order?
require
ar_not_empty: ar.is_empty = False
local
i: INTEGER
do
Result := True
from
i := ar.lower
until
i = ar.upper
loop
if ar [i] > ar [i + 1] then
Result := False
end
i := i + 1
end
end
feature
pancake_sort (ar: ARRAY [G]): ARRAY [G]
do
Result := sort (ar)
end
end
|
http://rosettacode.org/wiki/Sorting_algorithms/Stooge_sort | Sorting algorithms/Stooge sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
This page uses content from Wikipedia. The original article was at Stooge sort. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Show the Stooge Sort for an array of integers.
The Stooge Sort algorithm is as follows:
algorithm stoogesort(array L, i = 0, j = length(L)-1)
if L[j] < L[i] then
L[i] ↔ L[j]
if j - i > 1 then
t := (j - i + 1)/3
stoogesort(L, i , j-t)
stoogesort(L, i+t, j )
stoogesort(L, i , j-t)
return L
| #Maple | Maple | swap := proc(arr, a, b)
local temp := arr[a];
arr[a] := arr[b];
arr[b] := temp;
end proc:
stoogesort:= proc(arr, start_index, end_index)
local cur;
if (arr[end_index] < arr[start_index]) then
swap(arr, start_index, end_index);
end if;
if end_index - start_index > 1 then
cur := trunc((end_index - start_index + 1)/3);
stoogesort(arr, start_index, end_index - cur);
stoogesort(arr, start_index + cur, end_index);
stoogesort(arr, start_index, end_index - cur);
end if;
return arr;
end proc:
arr := Array([4, 2, 6, 1, 3, 7, 9, 5, 8]):
stoogesort(arr, 1, numelems(arr)); |
http://rosettacode.org/wiki/Sorting_algorithms/Stooge_sort | Sorting algorithms/Stooge sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
This page uses content from Wikipedia. The original article was at Stooge sort. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Show the Stooge Sort for an array of integers.
The Stooge Sort algorithm is as follows:
algorithm stoogesort(array L, i = 0, j = length(L)-1)
if L[j] < L[i] then
L[i] ↔ L[j]
if j - i > 1 then
t := (j - i + 1)/3
stoogesort(L, i , j-t)
stoogesort(L, i+t, j )
stoogesort(L, i , j-t)
return L
| #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | stoogeSort[lst_, I_, J_] := Module[{i = I, j = J, list = lst},
If[list[[j]] < list[[i]], list[[{i,j}]] = list[[{j,i}]];]
If[(j-i) > 1, t = Round[(j-i+1)/3];
list=stoogeSort[list,i,j-t];
list=stoogeSort[list,i+t,j];
list=stoogeSort[list,i,j-t];];
list
] |
http://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort | Sorting algorithms/Sleep sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
In general, sleep sort works by starting a separate task for each item to be sorted, where each task sleeps for an interval corresponding to the item's sort key, then emits the item. Items are then collected sequentially in time.
Task: Write a program that implements sleep sort. Have it accept non-negative integers on the command line and print the integers in sorted order. If this is not idomatic in your language or environment, input and output may be done differently. Enhancements for optimization, generalization, practicality, robustness, and so on are not required.
Sleep sort was presented anonymously on 4chan and has been discussed on Hacker News.
| #Prolog | Prolog | sleep_sort(L) :-
thread_pool_create(rosetta, 1024, []) ,
maplist(initsort, L, LID),
maplist(thread_join, LID, _LStatus),
thread_pool_destroy(rosetta).
initsort(V, Id) :-
thread_create_in_pool(rosetta, (sleep(V), writeln(V)), Id, []).
|
http://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort | Sorting algorithms/Sleep sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
In general, sleep sort works by starting a separate task for each item to be sorted, where each task sleeps for an interval corresponding to the item's sort key, then emits the item. Items are then collected sequentially in time.
Task: Write a program that implements sleep sort. Have it accept non-negative integers on the command line and print the integers in sorted order. If this is not idomatic in your language or environment, input and output may be done differently. Enhancements for optimization, generalization, practicality, robustness, and so on are not required.
Sleep sort was presented anonymously on 4chan and has been discussed on Hacker News.
| #PureBasic | PureBasic | NewMap threads()
Procedure Foo(n)
Delay(n)
PrintN(Str(n))
EndProcedure
If OpenConsole()
For i=1 To CountProgramParameters()
threads(Str(i)) = CreateThread(@Foo(), Val(ProgramParameter()))
Next
ForEach threads()
WaitThread(threads())
Next
Print("Press ENTER to exit"): Input()
EndIf |
http://rosettacode.org/wiki/Sorting_algorithms/Selection_sort | Sorting algorithms/Selection sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array (or list) of elements using the Selection sort algorithm.
It works as follows:
First find the smallest element in the array and exchange it with the element in the first position, then find the second smallest element and exchange it with the element in the second position, and continue in this way until the entire array is sorted.
Its asymptotic complexity is O(n2) making it inefficient on large arrays.
Its primary purpose is for when writing data is very expensive (slow) when compared to reading, eg. writing to flash memory or EEPROM.
No other sorting algorithm has less data movement.
References
Rosetta Code: O (complexity).
Wikipedia: Selection sort.
Wikipedia: [Big O notation].
| #E | E | def selectionSort := {
def cswap(c, a, b) {
def t := c[a]
c[a] := c[b]
c[b] := t
println(c)
}
def indexOfMin(array, first, last) {
var min := array[first]
var mini := first
for i in (first+1)..last {
if (array[i] < min) {
min := array[i]
mini := i
}
}
return mini
}
/** Selection sort (in-place). */
def selectionSort(array) {
def last := (array.size()-1)
for i in 0..(last - 1) {
cswap(array, i, indexOfMin(array, i + 1, last))
}
}
} |
http://rosettacode.org/wiki/Soundex | Soundex | Soundex is an algorithm for creating indices for words based on their pronunciation.
Task
The goal is for homophones to be encoded to the same representation so that they can be matched despite minor differences in spelling (from the soundex Wikipedia article).
Caution
There is a major issue in many of the implementations concerning the separation of two consonants that have the same soundex code! According to the official Rules [[1]]. So check for instance if Ashcraft is coded to A-261.
If a vowel (A, E, I, O, U) separates two consonants that have the same soundex code, the consonant to the right of the vowel is coded. Tymczak is coded as T-522 (T, 5 for the M, 2 for the C, Z ignored (see "Side-by-Side" rule above), 2 for the K). Since the vowel "A" separates the Z and K, the K is coded.
If "H" or "W" separate two consonants that have the same soundex code, the consonant to the right of the vowel is not coded. Example: Ashcraft is coded A-261 (A, 2 for the S, C ignored, 6 for the R, 1 for the F). It is not coded A-226.
| #Erlang | Erlang | -module(soundex).
-export([soundex/1]).
soundex([]) ->
[];
soundex(Str) ->
[Head|Tail] = string:to_upper(Str),
[Head | isoundex(Tail, [], todigit(Head))].
isoundex([], Acc, _) ->
case length(Acc) of
N when N == 3 ->
lists:reverse(Acc);
N when N < 3 ->
isoundex([], [$0 | Acc], ignore);
N when N > 3 ->
isoundex([], lists:sublist(Acc, N-2, N), ignore)
end;
isoundex([Head|Tail], Acc, Lastn) ->
Dig = todigit(Head),
case Dig of
Dig when Dig /= $0, Dig /= Lastn ->
isoundex(Tail, [Dig | Acc], Dig);
_ ->
case Head of
$H ->
isoundex(Tail, Acc, Lastn);
$W ->
isoundex(Tail, Acc, Lastn);
N when N >= $A, N =< $Z ->
isoundex(Tail, Acc, Dig);
_ ->
isoundex(Tail, Acc, Lastn) % This clause handles non alpha characters
end
end.
todigit(Chr) ->
Digits = "01230120022455012623010202",
HeadOff = Chr - $A + 1,
case HeadOff of
N when N > 0, N < 27 ->
lists:nth(HeadOff, Digits);
_ -> % Treat non alpha characters as a vowel
$0
end.
|
http://rosettacode.org/wiki/Sorting_algorithms/Shell_sort | Sorting algorithms/Shell sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array of elements using the Shell sort algorithm, a diminishing increment sort.
The Shell sort (also known as Shellsort or Shell's method) is named after its inventor, Donald Shell, who published the algorithm in 1959.
Shell sort is a sequence of interleaved insertion sorts based on an increment sequence.
The increment size is reduced after each pass until the increment size is 1.
With an increment size of 1, the sort is a basic insertion sort, but by this time the data is guaranteed to be almost sorted, which is insertion sort's "best case".
Any sequence will sort the data as long as it ends in 1, but some work better than others.
Empirical studies have shown a geometric increment sequence with a ratio of about 2.2 work well in practice.
[1]
Other good sequences are found at the On-Line Encyclopedia of Integer Sequences.
| #J | J | gaps =: [: }: 1 (1+3*])^:(> {:)^:a:~ #
insert =: (I.~ {. ]) , [ , ] }.~ I.~
gapinss =: #@] {. ,@|:@(] insert//.~ #@] $ i.@[)
shellSort =: [: ; gapinss &.>/@(< ,~ ]&.>@gaps) |
http://rosettacode.org/wiki/Sorting_algorithms/Shell_sort | Sorting algorithms/Shell sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array of elements using the Shell sort algorithm, a diminishing increment sort.
The Shell sort (also known as Shellsort or Shell's method) is named after its inventor, Donald Shell, who published the algorithm in 1959.
Shell sort is a sequence of interleaved insertion sorts based on an increment sequence.
The increment size is reduced after each pass until the increment size is 1.
With an increment size of 1, the sort is a basic insertion sort, but by this time the data is guaranteed to be almost sorted, which is insertion sort's "best case".
Any sequence will sort the data as long as it ends in 1, but some work better than others.
Empirical studies have shown a geometric increment sequence with a ratio of about 2.2 work well in practice.
[1]
Other good sequences are found at the On-Line Encyclopedia of Integer Sequences.
| #Java | Java | public static void shell(int[] a) {
int increment = a.length / 2;
while (increment > 0) {
for (int i = increment; i < a.length; i++) {
int j = i;
int temp = a[i];
while (j >= increment && a[j - increment] > temp) {
a[j] = a[j - increment];
j = j - increment;
}
a[j] = temp;
}
if (increment == 2) {
increment = 1;
} else {
increment *= (5.0 / 11);
}
}
} |
http://rosettacode.org/wiki/Stable_marriage_problem | Stable marriage problem | Solve the Stable marriage problem using the Gale/Shapley algorithm.
Problem description
Given an equal number of men and women to be paired for marriage, each man ranks all the women in order of his preference and each woman ranks all the men in order of her preference.
A stable set of engagements for marriage is one where no man prefers a woman over the one he is engaged to, where that other woman also prefers that man over the one she is engaged to. I.e. with consulting marriages, there would be no reason for the engagements between the people to change.
Gale and Shapley proved that there is a stable set of engagements for any set of preferences and the first link above gives their algorithm for finding a set of stable engagements.
Task Specifics
Given ten males:
abe, bob, col, dan, ed, fred, gav, hal, ian, jon
And ten females:
abi, bea, cath, dee, eve, fay, gay, hope, ivy, jan
And a complete list of ranked preferences, where the most liked is to the left:
abe: abi, eve, cath, ivy, jan, dee, fay, bea, hope, gay
bob: cath, hope, abi, dee, eve, fay, bea, jan, ivy, gay
col: hope, eve, abi, dee, bea, fay, ivy, gay, cath, jan
dan: ivy, fay, dee, gay, hope, eve, jan, bea, cath, abi
ed: jan, dee, bea, cath, fay, eve, abi, ivy, hope, gay
fred: bea, abi, dee, gay, eve, ivy, cath, jan, hope, fay
gav: gay, eve, ivy, bea, cath, abi, dee, hope, jan, fay
hal: abi, eve, hope, fay, ivy, cath, jan, bea, gay, dee
ian: hope, cath, dee, gay, bea, abi, fay, ivy, jan, eve
jon: abi, fay, jan, gay, eve, bea, dee, cath, ivy, hope
abi: bob, fred, jon, gav, ian, abe, dan, ed, col, hal
bea: bob, abe, col, fred, gav, dan, ian, ed, jon, hal
cath: fred, bob, ed, gav, hal, col, ian, abe, dan, jon
dee: fred, jon, col, abe, ian, hal, gav, dan, bob, ed
eve: jon, hal, fred, dan, abe, gav, col, ed, ian, bob
fay: bob, abe, ed, ian, jon, dan, fred, gav, col, hal
gay: jon, gav, hal, fred, bob, abe, col, ed, dan, ian
hope: gav, jon, bob, abe, ian, dan, hal, ed, col, fred
ivy: ian, col, hal, gav, fred, bob, abe, ed, jon, dan
jan: ed, hal, gav, abe, bob, jon, col, ian, fred, dan
Use the Gale Shapley algorithm to find a stable set of engagements
Perturb this set of engagements to form an unstable set of engagements then check this new set for stability.
References
The Stable Marriage Problem. (Eloquent description and background information).
Gale-Shapley Algorithm Demonstration.
Another Gale-Shapley Algorithm Demonstration.
Stable Marriage Problem - Numberphile (Video).
Stable Marriage Problem (the math bit) (Video).
The Stable Marriage Problem and School Choice. (Excellent exposition)
| #Tcl | Tcl | package require Tcl 8.5
# Functions as aliases to standard commands
interp alias {} tcl::mathfunc::pos {} ::lsearch -exact
interp alias {} tcl::mathfunc::nonempty {} ::llength
# The stability check
proc check engaged {
global preferences
set inverse [lreverse $engaged]
set errmsg "%s and %s like each other better than their present partners,\
%s and %s respectively"
dict for {she he} $engaged {
set shelikes [dict get $preferences $she]
set shelikesbetter [lrange $shelikes 0 [expr {pos($shelikes,$he)}]]
set helikes [dict get $preferences $he]
set helikesbetter [lrange $helikes 0 [expr {pos($helikes,$she)}]]
foreach guy $shelikesbetter {
set guysgirl [dict get $inverse $guy]
set guylikes [dict get $preferences $guy]
if {pos($guylikes,$guysgirl) > pos($guylikes,$she)} {
puts [format $errmsg $she $guy $he $guysgirl]
return 0
}
}
foreach gal $helikesbetter {
set galsguy [dict get $engaged $gal]
set gallikes [dict get $preferences $gal]
if {pos($gallikes,$galsguy) > pos($gallikes,$he)} {
puts [format $errmsg $he $gal $she $galsguy]
return 0
}
}
}
return 1
}
# The match-making algorithm
proc matchmaker {} {
global guys gals preferences
set guysfree $guys
set engaged {}
array set p $preferences
while {nonempty($guysfree)} {
set guysfree [lassign $guysfree guy]
set p($guy) [set guyslist [lassign $p($guy) gal]]
if {![dict exists $engaged $gal]} {
# She's free
dict set engaged $gal $guy
puts " $guy and $gal"
continue
}
# The bounder proposes to an engaged lass!
set fiance [dict get $engaged $gal]
if {pos($p($gal), $fiance) > pos($p($gal), $guy)} {
# She prefers the new guy
dict set engaged $gal $guy
puts " $gal dumped $fiance for $guy"
set guy $fiance
}
if {nonempty($p($guy))} {
lappend guysfree $guy
}
}
return $engaged
}
# Problem dataset; preferences unified since all names distinct
set guys {abe bob col dan ed fred gav hal ian jon}
set gals {abi bea cath dee eve fay gay hope ivy jan}
set preferences {
abe {abi eve cath ivy jan dee fay bea hope gay}
bob {cath hope abi dee eve fay bea jan ivy gay}
col {hope eve abi dee bea fay ivy gay cath jan}
dan {ivy fay dee gay hope eve jan bea cath abi}
ed {jan dee bea cath fay eve abi ivy hope gay}
fred {bea abi dee gay eve ivy cath jan hope fay}
gav {gay eve ivy bea cath abi dee hope jan fay}
hal {abi eve hope fay ivy cath jan bea gay dee}
ian {hope cath dee gay bea abi fay ivy jan eve}
jon {abi fay jan gay eve bea dee cath ivy hope}
abi {bob fred jon gav ian abe dan ed col hal}
bea {bob abe col fred gav dan ian ed jon hal}
cath {fred bob ed gav hal col ian abe dan jon}
dee {fred jon col abe ian hal gav dan bob ed}
eve {jon hal fred dan abe gav col ed ian bob}
fay {bob abe ed ian jon dan fred gav col hal}
gay {jon gav hal fred bob abe col ed dan ian}
hope {gav jon bob abe ian dan hal ed col fred}
ivy {ian col hal gav fred bob abe ed jon dan}
jan {ed hal gav abe bob jon col ian fred dan}
}
# The demonstration code
puts "Engagements:"
set engaged [matchmaker]
puts "\nCouples:"
set pfx ""
foreach gal $gals {
puts -nonewline "$pfx $gal is engaged to [dict get $engaged $gal]"
set pfx ",\n"
}
puts "\n"
puts "Engagement stability check [lindex {FAILED PASSED} [check $engaged]]"
puts "\n\nSwapping two fiances to introduce an error"
set tmp [dict get $engaged [lindex $gals 0]]
dict set engaged [lindex $gals 0] [dict get $engaged [lindex $gals 1]]
dict set engaged [lindex $gals 1] $tmp
foreach gal [lrange $gals 0 1] {
puts " $gal is now engaged to [dict get $engaged $gal]"
}
puts ""
puts "Engagement stability check [lindex {FAILED PASSED} [check $engaged]]" |
http://rosettacode.org/wiki/Stack | Stack |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also called LIFO.
The stack is accessed through its top.
The basic stack operations are:
push stores a new element onto the stack top;
pop returns the last pushed stack element, while removing it from the stack;
empty tests if the stack contains no elements.
Sometimes the last pushed stack element is made accessible for immutable access (for read) or mutable access (for write):
top (sometimes called peek to keep with the p theme) returns the topmost element without modifying the stack.
Stacks allow a very simple hardware implementation.
They are common in almost all processors.
In programming, stacks are also very popular for their way (LIFO) of resource management, usually memory.
Nested scopes of language objects are naturally implemented by a stack (sometimes by multiple stacks).
This is a classical way to implement local variables of a re-entrant or recursive subprogram. Stacks are also used to describe a formal computational framework.
See stack machine.
Many algorithms in pattern matching, compiler construction (e.g. recursive descent parsers), and machine learning (e.g. based on tree traversal) have a natural representation in terms of stacks.
Task
Create a stack supporting the basic operations: push, pop, empty.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
| #Liberty_BASIC | Liberty BASIC |
global stack$
stack$=""
randomize .51
for i = 1 to 10
if rnd(1)>0.5 then
print "pop => ";pop$()
else
j=j+1
s$ = chr$(j + 64)
print "push ";s$
call push s$
end if
next
print
print "Clean-up"
do
print "pop => ";pop$()
loop while not(empty())
print "Stack is empty"
end
'------------------------------------
sub push s$
stack$=s$+"|"+stack$ 'stack
end sub
function pop$()
if stack$="" then pop$="*EMPTY*": exit function
pop$=word$(stack$,1,"|")
stack$=mid$(stack$,instr(stack$,"|")+1)
end function
function empty()
empty =(stack$="")
end function
|
http://rosettacode.org/wiki/Spiral_matrix | Spiral matrix | Task
Produce a spiral array.
A spiral array is a square arrangement of the first N2 natural numbers, where the
numbers increase sequentially as you go around the edges of the array spiraling inwards.
For example, given 5, produce this array:
0 1 2 3 4
15 16 17 18 5
14 23 24 19 6
13 22 21 20 7
12 11 10 9 8
Related tasks
Zig-zag matrix
Identity_matrix
Ulam_spiral_(for_primes)
| #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | AddSquareRing[x_List/;Equal@@Dimensions[x] && Length[Dimensions[x]]==2]:=Module[{new=x,size,smallest},
size=Length[x];
smallest=x[[1,1]];
Do[
new[[i]]=Prepend[new[[i]],smallest-i];
new[[i]]=Append[new[[i]],smallest-3 size+i-3]
,{i,size}];
PrependTo[new,Range[smallest-3size-3-size-1,smallest-3size-3]];
AppendTo[new,Range[smallest-size-1,smallest-size-size-2,-1]];
new
]
MakeSquareSpiral[size_Integer/;size>0]:=Module[{largest,start,times},
start=size^2+If[Mod[size,2]==0,{{-4,-3},{-1,-2}},{{-1}}];
times=If[Mod[size,2]==0,size/2-1,(size-1)/2];
Nest[AddSquareRing,start,times]
] |
http://rosettacode.org/wiki/Sorting_algorithms/Radix_sort | Sorting algorithms/Radix sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an integer array with the radix sort algorithm.
The primary purpose is to complete the characterization of sort algorithms task.
| #J | J |
radixSortR =: 3 : 0 NB. base radixSort data
16 radixSortR y
:
keys =. x #.^:_1 y NB. compute keys
length =. #{.keys
extra =. (-length) {."0 buckets =. i.x
for_pass. i.-length do.
keys =. ; (buckets,pass{"1 keys) <@:}./.extra,keys
end.
x#.keys NB. restore the data
) |
http://rosettacode.org/wiki/Sorting_algorithms/Radix_sort | Sorting algorithms/Radix sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an integer array with the radix sort algorithm.
The primary purpose is to complete the characterization of sort algorithms task.
| #Java | Java | public static int[] sort(int[] old) {
// Loop for every bit in the integers
for (int shift = Integer.SIZE - 1; shift > -1; shift--) {
// The array to put the partially sorted array into
int[] tmp = new int[old.length];
// The number of 0s
int j = 0;
// Move the 0s to the new array, and the 1s to the old one
for (int i = 0; i < old.length; i++) {
// If there is a 1 in the bit we are testing, the number will be negative
boolean move = old[i] << shift >= 0;
// If this is the last bit, negative numbers are actually lower
if (shift == 0 ? !move : move) {
tmp[j] = old[i];
j++;
} else {
// It's a 1, so stick it in the old array for now
old[i - j] = old[i];
}
}
// Copy over the 1s from the old array
for (int i = j; i < tmp.length; i++) {
tmp[i] = old[i - j];
}
// And now the tmp array gets switched for another round of sorting
old = tmp;
}
return old;
} |
http://rosettacode.org/wiki/Sorting_algorithms/Quicksort | Sorting algorithms/Quicksort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
This page uses content from Wikipedia. The original article was at Quicksort. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Sort an array (or list) elements using the quicksort algorithm.
The elements must have a strict weak order and the index of the array can be of any discrete type.
For languages where this is not possible, sort an array of integers.
Quicksort, also known as partition-exchange sort, uses these steps.
Choose any element of the array to be the pivot.
Divide all other elements (except the pivot) into two partitions.
All elements less than the pivot must be in the first partition.
All elements greater than the pivot must be in the second partition.
Use recursion to sort both partitions.
Join the first sorted partition, the pivot, and the second sorted partition.
The best pivot creates partitions of equal length (or lengths differing by 1).
The worst pivot creates an empty partition (for example, if the pivot is the first or last element of a sorted array).
The run-time of Quicksort ranges from O(n log n) with the best pivots, to O(n2) with the worst pivots, where n is the number of elements in the array.
This is a simple quicksort algorithm, adapted from Wikipedia.
function quicksort(array)
less, equal, greater := three empty arrays
if length(array) > 1
pivot := select any element of array
for each x in array
if x < pivot then add x to less
if x = pivot then add x to equal
if x > pivot then add x to greater
quicksort(less)
quicksort(greater)
array := concatenate(less, equal, greater)
A better quicksort algorithm works in place, by swapping elements within the array, to avoid the memory allocation of more arrays.
function quicksort(array)
if length(array) > 1
pivot := select any element of array
left := first index of array
right := last index of array
while left ≤ right
while array[left] < pivot
left := left + 1
while array[right] > pivot
right := right - 1
if left ≤ right
swap array[left] with array[right]
left := left + 1
right := right - 1
quicksort(array from first index to right)
quicksort(array from left to last index)
Quicksort has a reputation as the fastest sort. Optimized variants of quicksort are common features of many languages and libraries. One often contrasts quicksort with merge sort, because both sorts have an average time of O(n log n).
"On average, mergesort does fewer comparisons than quicksort, so it may be better when complicated comparison routines are used. Mergesort also takes advantage of pre-existing order, so it would be favored for using sort() to merge several sorted arrays. On the other hand, quicksort is often faster for small arrays, and on arrays of a few distinct values, repeated many times." — http://perldoc.perl.org/sort.html
Quicksort is at one end of the spectrum of divide-and-conquer algorithms, with merge sort at the opposite end.
Quicksort is a conquer-then-divide algorithm, which does most of the work during the partitioning and the recursive calls. The subsequent reassembly of the sorted partitions involves trivial effort.
Merge sort is a divide-then-conquer algorithm. The partioning happens in a trivial way, by splitting the input array in half. Most of the work happens during the recursive calls and the merge phase.
With quicksort, every element in the first partition is less than or equal to every element in the second partition. Therefore, the merge phase of quicksort is so trivial that it needs no mention!
This task has not specified whether to allocate new arrays, or sort in place. This task also has not specified how to choose the pivot element. (Common ways to are to choose the first element, the middle element, or the median of three elements.) Thus there is a variety among the following implementations.
| #Arc | Arc | (def qs (seq)
(if (empty seq) nil
(let pivot (car seq)
(join (qs (keep [< _ pivot] (cdr seq)))
(list pivot)
(qs (keep [>= _ pivot] (cdr seq))))))) |
http://rosettacode.org/wiki/Sorting_algorithms/Patience_sort | Sorting algorithms/Patience sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Sort an array of numbers (of any convenient size) into ascending order using Patience sorting.
Related task
Longest increasing subsequence
| #Haskell | Haskell | import Control.Monad.ST
import Control.Monad
import Data.Array.ST
import Data.List
import qualified Data.Set as S
newtype Pile a = Pile [a]
instance Eq a => Eq (Pile a) where
Pile (x:_) == Pile (y:_) = x == y
instance Ord a => Ord (Pile a) where
Pile (x:_) `compare` Pile (y:_) = x `compare` y
patienceSort :: Ord a => [a] -> [a]
patienceSort = mergePiles . sortIntoPiles where
sortIntoPiles :: Ord a => [a] -> [[a]]
sortIntoPiles lst = runST $ do
piles <- newSTArray (1, length lst) []
let bsearchPiles x len = aux 1 len where
aux lo hi | lo > hi = return lo
| otherwise = do
let mid = (lo + hi) `div` 2
m <- readArray piles mid
if head m < x then
aux (mid+1) hi
else
aux lo (mid-1)
f len x = do
i <- bsearchPiles x len
writeArray piles i . (x:) =<< readArray piles i
return $ if i == len+1 then len+1 else len
len <- foldM f 0 lst
e <- getElems piles
return $ take len e
where newSTArray :: Ix i => (i,i) -> e -> ST s (STArray s i e)
newSTArray = newArray
mergePiles :: Ord a => [[a]] -> [a]
mergePiles = unfoldr f . S.fromList . map Pile where
f pq = case S.minView pq of
Nothing -> Nothing
Just (Pile [x], pq') -> Just (x, pq')
Just (Pile (x:xs), pq') -> Just (x, S.insert (Pile xs) pq')
main :: IO ()
main = print $ patienceSort [4, 65, 2, -31, 0, 99, 83, 782, 1] |
http://rosettacode.org/wiki/Sorting_algorithms/Insertion_sort | Sorting algorithms/Insertion sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
This page uses content from Wikipedia. The original article was at Insertion sort. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
An O(n2) sorting algorithm which moves elements one at a time into the correct position.
The algorithm consists of inserting one element at a time into the previously sorted part of the array, moving higher ranked elements up as necessary.
To start off, the first (or smallest, or any arbitrary) element of the unsorted array is considered to be the sorted part.
Although insertion sort is an O(n2) algorithm, its simplicity, low overhead, good locality of reference and efficiency make it a good choice in two cases:
small n,
as the final finishing-off algorithm for O(n logn) algorithms such as mergesort and quicksort.
The algorithm is as follows (from wikipedia):
function insertionSort(array A)
for i from 1 to length[A]-1 do
value := A[i]
j := i-1
while j >= 0 and A[j] > value do
A[j+1] := A[j]
j := j-1
done
A[j+1] = value
done
Writing the algorithm for integers will suffice.
| #ActionScript | ActionScript | function insertionSort(array:Array)
{
for(var i:int = 1; i < array.length;i++)
{
var value = array[i];
var j:int = i-1;
while(j >= 0 && array[j] > value)
{
array[j+1] = array[j];
j--;
}
array[j+1] = value;
}
return array;
} |
http://rosettacode.org/wiki/Sorting_algorithms/Permutation_sort | Sorting algorithms/Permutation sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Implement a permutation sort, which proceeds by generating the possible permutations
of the input array/list until discovering the sorted one.
Pseudocode:
while not InOrder(list) do
nextPermutation(list)
done
| #MATLAB_.2F_Octave | MATLAB / Octave | function list = permutationSort(list)
permutations = perms(1:numel(list)); %Generate all permutations of the item indicies
%Test every permutation of the indicies of the original list
for i = (1:size(permutations,1))
if issorted( list(permutations(i,:)) )
list = list(permutations(i,:));
return %Once the correct permutation of the original list is found break out of the program
end
end
end |
http://rosettacode.org/wiki/Sorting_algorithms/Permutation_sort | Sorting algorithms/Permutation sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Implement a permutation sort, which proceeds by generating the possible permutations
of the input array/list until discovering the sorted one.
Pseudocode:
while not InOrder(list) do
nextPermutation(list)
done
| #MAXScript | MAXScript | fn inOrder arr =
(
if arr.count < 2 then return true
else
(
local i = 1
while i < arr.count do
(
if arr[i+1] < arr[i] do return false
i += 1
)
return true
)
)
fn permutations arr =
(
if arr.count <= 1 then return arr
else
(
for i = 1 to arr.count do
(
local rest = for r in 1 to arr.count where r != i collect arr[r]
local permRest = permutations rest
local new = join #(arr[i]) permRest
if inOrder new do return new
)
)
) |
http://rosettacode.org/wiki/Sorting_algorithms/Pancake_sort | Sorting algorithms/Pancake sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array of integers (of any convenient size) into ascending order using Pancake sorting.
In short, instead of individual elements being sorted, the only operation allowed is to "flip" one end of the list, like so:
Before: 6 7 8 9 2 5 3 4 1
After: 9 8 7 6 2 5 3 4 1
Only one end of the list can be flipped; this should be the low end, but the high end is okay if it's easier to code or works better, but it must be the same end for the entire solution. (The end flipped can't be arbitrarily changed.)
Show both the initial, unsorted list and the final sorted list.
(Intermediate steps during sorting are optional.)
Optimizations are optional (but recommended).
Related tasks
Number reversal game
Topswops
Also see
Wikipedia article: pancake sorting.
| #Elena | Elena | import extensions;
extension op
{
pancakeSort()
{
var list := self.clone();
int i := list.Length;
if (i < 2) { ^ self };
while (i > 1)
{
int max_num_pos := 0;
int a := 0;
while (a < i)
{
if (list[a] > list[max_num_pos])
{
max_num_pos := a
};
a += 1
};
if (max_num_pos == i - 1)
{
}
else
{
if (max_num_pos > 0)
{
list.flip(list.Length, max_num_pos + 1)
};
list.flip(list.Length, i)
};
i -= 1
};
^ list
}
flip(int length, int num)
{
int i := 0;
int count := num - 1;
while (i < count)
{
var swap := self[i];
self[i] := self[count];
self[count] := swap;
i += 1;
count -= 1
}
}
}
public program()
{
var list := new int[]{6, 7, 8, 9, 2, 5, 3, 4, 1};
console.printLine("before:", list.asEnumerable());
console.printLine("after :", list.pancakeSort().asEnumerable())
} |
http://rosettacode.org/wiki/Sorting_algorithms/Pancake_sort | Sorting algorithms/Pancake sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array of integers (of any convenient size) into ascending order using Pancake sorting.
In short, instead of individual elements being sorted, the only operation allowed is to "flip" one end of the list, like so:
Before: 6 7 8 9 2 5 3 4 1
After: 9 8 7 6 2 5 3 4 1
Only one end of the list can be flipped; this should be the low end, but the high end is okay if it's easier to code or works better, but it must be the same end for the entire solution. (The end flipped can't be arbitrarily changed.)
Show both the initial, unsorted list and the final sorted list.
(Intermediate steps during sorting are optional.)
Optimizations are optional (but recommended).
Related tasks
Number reversal game
Topswops
Also see
Wikipedia article: pancake sorting.
| #Elixir | Elixir | defmodule Sort do
def pancake_sort(list) when is_list(list), do: pancake_sort(list, length(list))
defp pancake_sort(list, 0), do: list
defp pancake_sort(list, limit) do
index = search_max(list, limit)
flip(list, index) |> flip(limit) |> pancake_sort(limit-1)
end
defp search_max([h | t], limit), do: search_max(t, limit, 2, h, 1)
defp search_max(_, limit, index, _, max_index) when limit<index, do: max_index
defp search_max([h | t], limit, index, max, max_index) do
if h > max, do: search_max(t, limit, index+1, h, index),
else: search_max(t, limit, index+1, max, max_index)
end
defp flip(list, n), do: flip(list, n, [])
defp flip(list, 0, reverse), do: reverse ++ list
defp flip([h | t], n, reverse) do
flip(t, n-1, [h | reverse])
end
end
IO.inspect list = Enum.shuffle(1..9)
IO.inspect Sort.pancake_sort(list) |
http://rosettacode.org/wiki/Sorting_algorithms/Stooge_sort | Sorting algorithms/Stooge sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
This page uses content from Wikipedia. The original article was at Stooge sort. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Show the Stooge Sort for an array of integers.
The Stooge Sort algorithm is as follows:
algorithm stoogesort(array L, i = 0, j = length(L)-1)
if L[j] < L[i] then
L[i] ↔ L[j]
if j - i > 1 then
t := (j - i + 1)/3
stoogesort(L, i , j-t)
stoogesort(L, i+t, j )
stoogesort(L, i , j-t)
return L
| #MATLAB_.2F_Octave | MATLAB / Octave | %Required inputs:
%i = 1
%j = length(list)
%
function list = stoogeSort(list,i,j)
if list(j) < list(i)
list([i j]) = list([j i]);
end
if (j - i) > 1
t = round((j-i+1)/3);
list = stoogeSort(list,i,j-t);
list = stoogeSort(list,i+t,j);
list = stoogeSort(list,i,j-t);
end
end |
http://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort | Sorting algorithms/Sleep sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
In general, sleep sort works by starting a separate task for each item to be sorted, where each task sleeps for an interval corresponding to the item's sort key, then emits the item. Items are then collected sequentially in time.
Task: Write a program that implements sleep sort. Have it accept non-negative integers on the command line and print the integers in sorted order. If this is not idomatic in your language or environment, input and output may be done differently. Enhancements for optimization, generalization, practicality, robustness, and so on are not required.
Sleep sort was presented anonymously on 4chan and has been discussed on Hacker News.
| #Python | Python | from time import sleep
from threading import Timer
def sleepsort(values):
sleepsort.result = []
def add1(x):
sleepsort.result.append(x)
mx = values[0]
for v in values:
if mx < v: mx = v
Timer(v, add1, [v]).start()
sleep(mx+1)
return sleepsort.result
if __name__ == '__main__':
x = [3,2,4,7,3,6,9,1]
if sleepsort(x) == sorted(x):
print('sleep sort worked for:',x)
else:
print('sleep sort FAILED for:',x) |
http://rosettacode.org/wiki/Sorting_algorithms/Selection_sort | Sorting algorithms/Selection sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array (or list) of elements using the Selection sort algorithm.
It works as follows:
First find the smallest element in the array and exchange it with the element in the first position, then find the second smallest element and exchange it with the element in the second position, and continue in this way until the entire array is sorted.
Its asymptotic complexity is O(n2) making it inefficient on large arrays.
Its primary purpose is for when writing data is very expensive (slow) when compared to reading, eg. writing to flash memory or EEPROM.
No other sorting algorithm has less data movement.
References
Rosetta Code: O (complexity).
Wikipedia: Selection sort.
Wikipedia: [Big O notation].
| #EasyLang | EasyLang | subr sort
for i = 0 to len data[] - 2
min_pos = i
for j = i + 1 to len data[] - 1
if data[j] < data[min_pos]
min_pos = j
.
.
swap data[i] data[min_pos]
.
.
data[] = [ 29 4 72 44 55 26 27 77 92 5 ]
call sort
print data[] |
http://rosettacode.org/wiki/Sorting_algorithms/Selection_sort | Sorting algorithms/Selection sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array (or list) of elements using the Selection sort algorithm.
It works as follows:
First find the smallest element in the array and exchange it with the element in the first position, then find the second smallest element and exchange it with the element in the second position, and continue in this way until the entire array is sorted.
Its asymptotic complexity is O(n2) making it inefficient on large arrays.
Its primary purpose is for when writing data is very expensive (slow) when compared to reading, eg. writing to flash memory or EEPROM.
No other sorting algorithm has less data movement.
References
Rosetta Code: O (complexity).
Wikipedia: Selection sort.
Wikipedia: [Big O notation].
| #EchoLisp | EchoLisp |
;; recursive version (adapted from Racket)
(lib 'list) ;; list-delete
(define (sel-sort xs (x0))
(cond
[(null? xs) null]
[else (set! x0 (apply min xs))
(cons x0 (sel-sort (list-delete xs x0)))]))
(sel-sort (shuffle (iota 13)))
→ (0 1 2 3 4 5 6 7 8 9 10 11 12)
;; straightforward and more efficient implementation using list-swap!
(define (sel-sort list)
(maplist (lambda( L)
(first (list-swap! L (first L) (apply min L )))) list))
(sel-sort (shuffle (iota 13)))
→ (0 1 2 3 4 5 6 7 8 9 10 11 12)
|
http://rosettacode.org/wiki/Soundex | Soundex | Soundex is an algorithm for creating indices for words based on their pronunciation.
Task
The goal is for homophones to be encoded to the same representation so that they can be matched despite minor differences in spelling (from the soundex Wikipedia article).
Caution
There is a major issue in many of the implementations concerning the separation of two consonants that have the same soundex code! According to the official Rules [[1]]. So check for instance if Ashcraft is coded to A-261.
If a vowel (A, E, I, O, U) separates two consonants that have the same soundex code, the consonant to the right of the vowel is coded. Tymczak is coded as T-522 (T, 5 for the M, 2 for the C, Z ignored (see "Side-by-Side" rule above), 2 for the K). Since the vowel "A" separates the Z and K, the K is coded.
If "H" or "W" separate two consonants that have the same soundex code, the consonant to the right of the vowel is not coded. Example: Ashcraft is coded A-261 (A, 2 for the S, C ignored, 6 for the R, 1 for the F). It is not coded A-226.
| #F.23 | F# | module Soundex
let soundex (s : string) =
let code c =
match c with
| 'B' | 'F' | 'P' | 'V' -> Some('1')
| 'C' | 'G' | 'J' | 'K' | 'Q' | 'S' | 'X' | 'Z' -> Some('2')
| 'D' | 'T' -> Some('3')
| 'L' -> Some('4')
| 'M' | 'N' -> Some('5')
| 'R' -> Some('6')
| _ -> None
let rec p l =
match l with
| [] -> []
| x :: y :: tail when (code x) = (code y) -> (p (y :: tail))
| x :: 'W' :: y :: tail when (code x) = (code y) -> (p (y :: tail))
| x :: 'H' :: y :: tail when (code x) = (code y) -> (p (y :: tail))
| x :: tail -> (code x) :: (p tail)
let chars =
match (p (s.ToUpper() |> List.ofSeq)) with
| [] -> ""
| head :: tail -> new string((s.[0] :: (tail |> List.filter (fun x -> x.IsSome) |> List.map (fun x -> x.Value))) |> List.toArray)
chars.PadRight(4, '0').Substring(0, 4)
let test (input, se) =
printfn "%12s\t%s\t%s" input se (soundex input)
let testCases = [|
("Ashcraft", "A261"); ("Ashcroft", "A261"); ("Burroughs", "B620"); ("Burrows", "B620");
("Ekzampul", "E251"); ("Example", "E251"); ("Ellery", "E460"); ("Euler", "E460");
("Ghosh", "G200"); ("Gauss", "G200"); ("Gutierrez", "G362"); ("Heilbronn", "H416");
("Hilbert", "H416"); ("Jackson", "J250"); ("Kant", "K530"); ("Knuth", "K530");
("Lee", "L000"); ("Lukasiewicz", "L222"); ("Lissajous", "L222"); ("Ladd", "L300");
("Lloyd", "L300"); ("Moses", "M220"); ("O'Hara", "O600"); ("Pfister", "P236");
("Rubin", "R150"); ("Robert", "R163"); ("Rupert", "R163"); ("Soundex", "S532");
("Sownteks", "S532"); ("Tymczak", "T522"); ("VanDeusen", "V532"); ("Washington", "W252");
("Wheaton", "W350");
|]
[<EntryPoint>]
let main args =
testCases |> Array.sortBy (fun (_, x) -> x) |> Array.iter test
System.Console.ReadLine() |> ignore
0
|
http://rosettacode.org/wiki/Sorting_algorithms/Shell_sort | Sorting algorithms/Shell sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array of elements using the Shell sort algorithm, a diminishing increment sort.
The Shell sort (also known as Shellsort or Shell's method) is named after its inventor, Donald Shell, who published the algorithm in 1959.
Shell sort is a sequence of interleaved insertion sorts based on an increment sequence.
The increment size is reduced after each pass until the increment size is 1.
With an increment size of 1, the sort is a basic insertion sort, but by this time the data is guaranteed to be almost sorted, which is insertion sort's "best case".
Any sequence will sort the data as long as it ends in 1, but some work better than others.
Empirical studies have shown a geometric increment sequence with a ratio of about 2.2 work well in practice.
[1]
Other good sequences are found at the On-Line Encyclopedia of Integer Sequences.
| #JavaScript | JavaScript | function shellSort (a) {
for (var h = a.length; h > 0; h = parseInt(h / 2)) {
for (var i = h; i < a.length; i++) {
var k = a[i];
for (var j = i; j >= h && k < a[j - h]; j -= h)
a[j] = a[j - h];
a[j] = k;
}
}
return a;
}
var a = [];
var n = location.href.match(/\?(\d+)|$/)[1] || 10;
for (var i = 0; i < n; i++)
a.push(parseInt(Math.random() * 100));
shellSort(a);
document.write(a.join(" ")); |
http://rosettacode.org/wiki/Stable_marriage_problem | Stable marriage problem | Solve the Stable marriage problem using the Gale/Shapley algorithm.
Problem description
Given an equal number of men and women to be paired for marriage, each man ranks all the women in order of his preference and each woman ranks all the men in order of her preference.
A stable set of engagements for marriage is one where no man prefers a woman over the one he is engaged to, where that other woman also prefers that man over the one she is engaged to. I.e. with consulting marriages, there would be no reason for the engagements between the people to change.
Gale and Shapley proved that there is a stable set of engagements for any set of preferences and the first link above gives their algorithm for finding a set of stable engagements.
Task Specifics
Given ten males:
abe, bob, col, dan, ed, fred, gav, hal, ian, jon
And ten females:
abi, bea, cath, dee, eve, fay, gay, hope, ivy, jan
And a complete list of ranked preferences, where the most liked is to the left:
abe: abi, eve, cath, ivy, jan, dee, fay, bea, hope, gay
bob: cath, hope, abi, dee, eve, fay, bea, jan, ivy, gay
col: hope, eve, abi, dee, bea, fay, ivy, gay, cath, jan
dan: ivy, fay, dee, gay, hope, eve, jan, bea, cath, abi
ed: jan, dee, bea, cath, fay, eve, abi, ivy, hope, gay
fred: bea, abi, dee, gay, eve, ivy, cath, jan, hope, fay
gav: gay, eve, ivy, bea, cath, abi, dee, hope, jan, fay
hal: abi, eve, hope, fay, ivy, cath, jan, bea, gay, dee
ian: hope, cath, dee, gay, bea, abi, fay, ivy, jan, eve
jon: abi, fay, jan, gay, eve, bea, dee, cath, ivy, hope
abi: bob, fred, jon, gav, ian, abe, dan, ed, col, hal
bea: bob, abe, col, fred, gav, dan, ian, ed, jon, hal
cath: fred, bob, ed, gav, hal, col, ian, abe, dan, jon
dee: fred, jon, col, abe, ian, hal, gav, dan, bob, ed
eve: jon, hal, fred, dan, abe, gav, col, ed, ian, bob
fay: bob, abe, ed, ian, jon, dan, fred, gav, col, hal
gay: jon, gav, hal, fred, bob, abe, col, ed, dan, ian
hope: gav, jon, bob, abe, ian, dan, hal, ed, col, fred
ivy: ian, col, hal, gav, fred, bob, abe, ed, jon, dan
jan: ed, hal, gav, abe, bob, jon, col, ian, fred, dan
Use the Gale Shapley algorithm to find a stable set of engagements
Perturb this set of engagements to form an unstable set of engagements then check this new set for stability.
References
The Stable Marriage Problem. (Eloquent description and background information).
Gale-Shapley Algorithm Demonstration.
Another Gale-Shapley Algorithm Demonstration.
Stable Marriage Problem - Numberphile (Video).
Stable Marriage Problem (the math bit) (Video).
The Stable Marriage Problem and School Choice. (Excellent exposition)
| #UNIX_Shell | UNIX Shell | #!/usr/bin/env bash
main() {
# Our ten males:
local males=(abe bob col dan ed fred gav hal ian jon)
# And ten females:
local females=(abi bea cath dee eve fay gay hope ivy jan)
# Everyone's preferences, ranked most to least desirable:
local abe=( abi eve cath ivy jan dee fay bea hope gay )
local abi=( bob fred jon gav ian abe dan ed col hal )
local bea=( bob abe col fred gav dan ian ed jon hal )
local bob=(cath hope abi dee eve fay bea jan ivy gay )
local cath=(fred bob ed gav hal col ian abe dan jon )
local col=(hope eve abi dee bea fay ivy gay cath jan )
local dan=( ivy fay dee gay hope eve jan bea cath abi )
local dee=(fred jon col abe ian hal gav dan bob ed )
local ed=( jan dee bea cath fay eve abi ivy hope gay )
local eve=( jon hal fred dan abe gav col ed ian bob )
local fay=( bob abe ed ian jon dan fred gav col hal )
local fred=( bea abi dee gay eve ivy cath jan hope fay )
local gav=( gay eve ivy bea cath abi dee hope jan fay )
local gay=( jon gav hal fred bob abe col ed dan ian )
local hal=( abi eve hope fay ivy cath jan bea gay dee )
local hope=( gav jon bob abe ian dan hal ed col fred)
local ian=(hope cath dee gay bea abi fay ivy jan eve )
local ivy=( ian col hal gav fred bob abe ed jon dan )
local jan=( ed hal gav abe bob jon col ian fred dan )
local jon=( abi fay jan gay eve bea dee cath ivy hope)
# A place to store the engagements:
local -A engagements=()
# Our list of free males, initially comprised of all of them:
local freemales=( "${males[@]}" )
# Now we use the Gale-Shapley algorithm to find a stable set of engagements
# Loop over the free males. Note that we can't use for..in because the body
# of the loop may modify the array we're looping over
local -i m=0
while (( m < ${#freemales[@]} )); do
local male=${freemales[m]}
let m+=1
# This guy's preferences
eval 'local his=("${'"$male"'[@]}")'
# Starting with his favorite
local -i f=0
local female=${his[f]}
# Find her preferences
eval 'local hers=("${'"$female"'[@]}")'
# And her current fiancé, if any
local fiance=${engagements[$female]}
# If she has a fiancé and prefers him to this guy, look for this guy's next
# best choice
while [[ -n $fiance ]] &&
(( $(index "$male" "${hers[@]}") > $(index "$fiance" "${hers[@]}") )); do
let f+=1
female=${his[f]}
eval 'hers=("${'"$female"'[@]}")'
fiance=${engagements[$female]}
done
# If we're still on someone who's engaged, it means she prefers this guy
# to her current fiancé. Dump him and put him at the end of the free list.
if [[ -n $fiance ]]; then
freemales+=("$fiance")
printf '%-4s rejected %-4s\n' "$female" "$fiance"
fi
# We found a match! Record it
engagements[$female]=$male
printf '%-4s accepted %-4s\n' "$female" "$male"
done
# Display the final result, which should be stable
print_couples engagements
# Verify its stability
print_stable engagements "${females[@]}"
# Try a swap
printf '\nWhat if cath and ivy swap partners?\n'
local temp=${engagements[cath]}
engagements[cath]=${engagements[ivy]}
engagements[ivy]=$temp
# Display the new result, which should be unstable
print_couples engagements
# Verify its instability
print_stable engagements "${females[@]}"
}
# utility function - get index of an item in an array
index() {
local needle=$1
shift
local haystack=("$@")
local -i i
for i in "${!haystack[@]}"; do
if [[ ${haystack[i]} == $needle ]]; then
printf '%d\n' "$i"
return 0
fi
done
return 1
}
# print the couples from the engagement array; takes name of array as argument
print_couples() {
printf '\nCouples:\n'
local keys
mapfile -t keys < <(eval 'printf '\''%s\n'\'' "${!'"$1"'[@]}"' | sort)
local female
for female in "${keys[@]}"; do
eval 'local male=${'"$1"'["'"$female"'"]}'
printf '%-4s is engaged to %-4s\n' "$female" "$male"
done
printf '\n'
}
# print whether a set of engagements is stable; takes name of engagement array
# followed by the list of females
print_stable() {
if stable "$@"; then
printf 'These couples are stable.\n'
else
printf 'These couples are not stable.\n'
fi
}
# determine if a set of engagements is stable; takes name of engagement array
# followed by the list of females
stable() {
local dict=$1
shift
eval 'local shes=("${!'"$dict"'[@]}")'
eval 'local hes=("${'"$dict"'[@]}")'
local -i i
local -i result=0
for (( i=0; i<${#shes[@]}; ++i )); do
local she=${shes[i]} he=${hes[i]}
eval 'local his=("${'"$he"'[@]}")'
local alt
for alt in "$@"; do
eval 'local fiance=${'"$dict"'["'"$alt"'"]}'
eval 'local hers=("${'"$alt"'[@]}")'
if (( $(index "$she" "${his[@]}") > $(index "$alt" "${his[@]}")
&& $(index "$fiance" "${hers[@]}") > $(index "$he" "${hers[@]}") ))
then
printf '%-4s is engaged to %-4s but prefers %4s, ' "$he" "$she" "$alt"
printf 'while %-4s is engaged to %-4s but prefers %4s.\n' "$alt" "$fiance" "$he"
result=1
fi
done
done
if (( result )); then printf '\n'; fi
return $result
}
main "$@" |
http://rosettacode.org/wiki/Stack | Stack |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also called LIFO.
The stack is accessed through its top.
The basic stack operations are:
push stores a new element onto the stack top;
pop returns the last pushed stack element, while removing it from the stack;
empty tests if the stack contains no elements.
Sometimes the last pushed stack element is made accessible for immutable access (for read) or mutable access (for write):
top (sometimes called peek to keep with the p theme) returns the topmost element without modifying the stack.
Stacks allow a very simple hardware implementation.
They are common in almost all processors.
In programming, stacks are also very popular for their way (LIFO) of resource management, usually memory.
Nested scopes of language objects are naturally implemented by a stack (sometimes by multiple stacks).
This is a classical way to implement local variables of a re-entrant or recursive subprogram. Stacks are also used to describe a formal computational framework.
See stack machine.
Many algorithms in pattern matching, compiler construction (e.g. recursive descent parsers), and machine learning (e.g. based on tree traversal) have a natural representation in terms of stacks.
Task
Create a stack supporting the basic operations: push, pop, empty.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
| #Lingo | Lingo | -- parent script "Stack"
property _tos
on push (me, data)
me._tos = [#data:data, #next:me._tos]
end
on pop (me)
if voidP(me._tos) then return VOID
data = me._tos.data
me._tos = me._tos.next
return data
end
on peek (me)
if voidP(me._tos) then return VOID
return me._tos.data
end
on empty (me)
return voidP(me.peek())
end |
http://rosettacode.org/wiki/Spiral_matrix | Spiral matrix | Task
Produce a spiral array.
A spiral array is a square arrangement of the first N2 natural numbers, where the
numbers increase sequentially as you go around the edges of the array spiraling inwards.
For example, given 5, produce this array:
0 1 2 3 4
15 16 17 18 5
14 23 24 19 6
13 22 21 20 7
12 11 10 9 8
Related tasks
Zig-zag matrix
Identity_matrix
Ulam_spiral_(for_primes)
| #MATLAB | MATLAB | function matrix = reverseSpiral(n)
matrix = (-spiral(n))+n^2;
if mod(n,2)==0
matrix = flipud(matrix);
else
matrix = fliplr(matrix);
end
end %reverseSpiral |
http://rosettacode.org/wiki/Sorting_algorithms/Radix_sort | Sorting algorithms/Radix sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an integer array with the radix sort algorithm.
The primary purpose is to complete the characterization of sort algorithms task.
| #jq | jq | # Sort the input array;
# "base" must be an integer greater than 1
def radix_sort(base):
# We only need the ceiling of non-negatives:
def ceil: if . == floor then . else (. + 1 | floor) end;
min as $min
| map(. - $min)
| ((( max|log) / (base|log)) | ceil) as $rounds
| reduce range(0; $rounds) as $i
# state: [ base^i, buckets ]
( [1, .];
.[0] as $base_i
| reduce .[1][] as $n
([];
(($n/$base_i) % base) as $digit
| .[$digit] += [$n] )
| [($base_i * base), (map(select(. != null)) | flatten)] )
| .[1]
| map(. + $min) ;
def radix_sort:
radix_sort(10);
|
http://rosettacode.org/wiki/Sorting_algorithms/Radix_sort | Sorting algorithms/Radix sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an integer array with the radix sort algorithm.
The primary purpose is to complete the characterization of sort algorithms task.
| #Julia | Julia | function radixsort(tobesorted::Vector{Int64})
arr = deepcopy(tobesorted)
for shift in 63:-1:0
tmp = Vector{Int64}(undef, length(arr))
j = 0
for i in 1:length(arr)
if (shift == 0) == ((arr[i] << shift) >= 0)
arr[i - j] = arr[i]
else
tmp[j + 1] = arr[i]
j += 1
end
end
tmp[j+1:end] .= arr[1:length(tmp)-j]
arr = tmp
end
arr
end
function testradixsort()
arrays = [[170, 45, 75, -90, -802, 24, 2, 66], [-4, 5, -26, 58, -990, 331, 331, 990, -1837, 2028]]
for array in arrays
println(radixsort(array))
end
end
testradixsort()
|
http://rosettacode.org/wiki/Sorting_algorithms/Quicksort | Sorting algorithms/Quicksort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
This page uses content from Wikipedia. The original article was at Quicksort. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Sort an array (or list) elements using the quicksort algorithm.
The elements must have a strict weak order and the index of the array can be of any discrete type.
For languages where this is not possible, sort an array of integers.
Quicksort, also known as partition-exchange sort, uses these steps.
Choose any element of the array to be the pivot.
Divide all other elements (except the pivot) into two partitions.
All elements less than the pivot must be in the first partition.
All elements greater than the pivot must be in the second partition.
Use recursion to sort both partitions.
Join the first sorted partition, the pivot, and the second sorted partition.
The best pivot creates partitions of equal length (or lengths differing by 1).
The worst pivot creates an empty partition (for example, if the pivot is the first or last element of a sorted array).
The run-time of Quicksort ranges from O(n log n) with the best pivots, to O(n2) with the worst pivots, where n is the number of elements in the array.
This is a simple quicksort algorithm, adapted from Wikipedia.
function quicksort(array)
less, equal, greater := three empty arrays
if length(array) > 1
pivot := select any element of array
for each x in array
if x < pivot then add x to less
if x = pivot then add x to equal
if x > pivot then add x to greater
quicksort(less)
quicksort(greater)
array := concatenate(less, equal, greater)
A better quicksort algorithm works in place, by swapping elements within the array, to avoid the memory allocation of more arrays.
function quicksort(array)
if length(array) > 1
pivot := select any element of array
left := first index of array
right := last index of array
while left ≤ right
while array[left] < pivot
left := left + 1
while array[right] > pivot
right := right - 1
if left ≤ right
swap array[left] with array[right]
left := left + 1
right := right - 1
quicksort(array from first index to right)
quicksort(array from left to last index)
Quicksort has a reputation as the fastest sort. Optimized variants of quicksort are common features of many languages and libraries. One often contrasts quicksort with merge sort, because both sorts have an average time of O(n log n).
"On average, mergesort does fewer comparisons than quicksort, so it may be better when complicated comparison routines are used. Mergesort also takes advantage of pre-existing order, so it would be favored for using sort() to merge several sorted arrays. On the other hand, quicksort is often faster for small arrays, and on arrays of a few distinct values, repeated many times." — http://perldoc.perl.org/sort.html
Quicksort is at one end of the spectrum of divide-and-conquer algorithms, with merge sort at the opposite end.
Quicksort is a conquer-then-divide algorithm, which does most of the work during the partitioning and the recursive calls. The subsequent reassembly of the sorted partitions involves trivial effort.
Merge sort is a divide-then-conquer algorithm. The partioning happens in a trivial way, by splitting the input array in half. Most of the work happens during the recursive calls and the merge phase.
With quicksort, every element in the first partition is less than or equal to every element in the second partition. Therefore, the merge phase of quicksort is so trivial that it needs no mention!
This task has not specified whether to allocate new arrays, or sort in place. This task also has not specified how to choose the pivot element. (Common ways to are to choose the first element, the middle element, or the median of three elements.) Thus there is a variety among the following implementations.
| #ARM_Assembly | ARM Assembly |
/* ARM assembly Raspberry PI */
/* program quickSort.s */
/* look pseudo code in wikipedia quicksort */
/************************************/
/* Constantes */
/************************************/
.equ STDOUT, 1 @ Linux output console
.equ EXIT, 1 @ Linux syscall
.equ WRITE, 4 @ Linux syscall
/*********************************/
/* Initialized data */
/*********************************/
.data
szMessSortOk: .asciz "Table sorted.\n"
szMessSortNok: .asciz "Table not sorted !!!!!.\n"
sMessResult: .ascii "Value : "
sMessValeur: .fill 11, 1, ' ' @ size => 11
szCarriageReturn: .asciz "\n"
.align 4
iGraine: .int 123456
.equ NBELEMENTS, 10
#TableNumber: .int 9,5,6,1,2,3,10,8,4,7
#TableNumber: .int 1,3,5,2,4,6,10,8,4,7
#TableNumber: .int 1,3,5,2,4,6,10,8,4,7
#TableNumber: .int 1,2,3,4,5,6,10,8,4,7
TableNumber: .int 10,9,8,7,6,5,4,3,2,1
#TableNumber: .int 13,12,11,10,9,8,7,6,5,4,3,2,1
/*********************************/
/* UnInitialized data */
/*********************************/
.bss
/*********************************/
/* code section */
/*********************************/
.text
.global main
main: @ entry of program
1:
ldr r0,iAdrTableNumber @ address number table
mov r1,#0 @ indice first item
mov r2,#NBELEMENTS @ number of élements
bl triRapide @ call quicksort
ldr r0,iAdrTableNumber @ address number table
bl displayTable
ldr r0,iAdrTableNumber @ address number table
mov r1,#NBELEMENTS @ number of élements
bl isSorted @ control sort
cmp r0,#1 @ sorted ?
beq 2f
ldr r0,iAdrszMessSortNok @ no !! error sort
bl affichageMess
b 100f
2: @ yes
ldr r0,iAdrszMessSortOk
bl affichageMess
100: @ standard end of the program
mov r0, #0 @ return code
mov r7, #EXIT @ request to exit program
svc #0 @ perform the system call
iAdrsMessValeur: .int sMessValeur
iAdrszCarriageReturn: .int szCarriageReturn
iAdrsMessResult: .int sMessResult
iAdrTableNumber: .int TableNumber
iAdrszMessSortOk: .int szMessSortOk
iAdrszMessSortNok: .int szMessSortNok
/******************************************************************/
/* control sorted table */
/******************************************************************/
/* r0 contains the address of table */
/* r1 contains the number of elements > 0 */
/* r0 return 0 if not sorted 1 if sorted */
isSorted:
push {r2-r4,lr} @ save registers
mov r2,#0
ldr r4,[r0,r2,lsl #2]
1:
add r2,#1
cmp r2,r1
movge r0,#1
bge 100f
ldr r3,[r0,r2, lsl #2]
cmp r3,r4
movlt r0,#0
blt 100f
mov r4,r3
b 1b
100:
pop {r2-r4,lr}
bx lr @ return
/***************************************************/
/* Appel récursif Tri Rapide quicksort */
/***************************************************/
/* r0 contains the address of table */
/* r1 contains index of first item */
/* r2 contains the number of elements > 0 */
triRapide:
push {r2-r5,lr} @ save registers
sub r2,#1 @ last item index
cmp r1,r2 @ first > last ?
bge 100f @ yes -> end
mov r4,r0 @ save r0
mov r5,r2 @ save r2
bl partition1 @ cutting into 2 parts
mov r2,r0 @ index partition
mov r0,r4 @ table address
bl triRapide @ sort lower part
add r1,r2,#1 @ index begin = index partition + 1
add r2,r5,#1 @ number of elements
bl triRapide @ sort higter part
100: @ end function
pop {r2-r5,lr} @ restaur registers
bx lr @ return
/******************************************************************/
/* Partition table elements */
/******************************************************************/
/* r0 contains the address of table */
/* r1 contains index of first item */
/* r2 contains index of last item */
partition1:
push {r1-r7,lr} @ save registers
ldr r3,[r0,r2,lsl #2] @ load value last index
mov r4,r1 @ init with first index
mov r5,r1 @ init with first index
1: @ begin loop
ldr r6,[r0,r5,lsl #2] @ load value
cmp r6,r3 @ compare value
ldrlt r7,[r0,r4,lsl #2] @ if < swap value table
strlt r6,[r0,r4,lsl #2]
strlt r7,[r0,r5,lsl #2]
addlt r4,#1 @ and increment index 1
add r5,#1 @ increment index 2
cmp r5,r2 @ end ?
blt 1b @ no loop
ldr r7,[r0,r4,lsl #2] @ swap value
str r3,[r0,r4,lsl #2]
str r7,[r0,r2,lsl #2]
mov r0,r4 @ return index partition
100:
pop {r1-r7,lr}
bx lr
/******************************************************************/
/* Display table elements */
/******************************************************************/
/* r0 contains the address of table */
displayTable:
push {r0-r3,lr} @ save registers
mov r2,r0 @ table address
mov r3,#0
1: @ loop display table
ldr r0,[r2,r3,lsl #2]
ldr r1,iAdrsMessValeur @ display value
bl conversion10 @ call function
ldr r0,iAdrsMessResult
bl affichageMess @ display message
add r3,#1
cmp r3,#NBELEMENTS - 1
ble 1b
ldr r0,iAdrszCarriageReturn
bl affichageMess
100:
pop {r0-r3,lr}
bx lr
/******************************************************************/
/* display text with size calculation */
/******************************************************************/
/* r0 contains the address of the message */
affichageMess:
push {r0,r1,r2,r7,lr} @ save registres
mov r2,#0 @ counter length
1: @ loop length calculation
ldrb r1,[r0,r2] @ read octet start position + index
cmp r1,#0 @ if 0 its over
addne r2,r2,#1 @ else add 1 in the length
bne 1b @ and loop
@ so here r2 contains the length of the message
mov r1,r0 @ address message in r1
mov r0,#STDOUT @ code to write to the standard output Linux
mov r7, #WRITE @ code call system "write"
svc #0 @ call systeme
pop {r0,r1,r2,r7,lr} @ restaur des 2 registres */
bx lr @ return
/******************************************************************/
/* Converting a register to a decimal unsigned */
/******************************************************************/
/* r0 contains value and r1 address area */
/* r0 return size of result (no zero final in area) */
/* area size => 11 bytes */
.equ LGZONECAL, 10
conversion10:
push {r1-r4,lr} @ save registers
mov r3,r1
mov r2,#LGZONECAL
1: @ start loop
bl divisionpar10U @ unsigned r0 <- dividende. quotient ->r0 reste -> r1
add r1,#48 @ digit
strb r1,[r3,r2] @ store digit on area
cmp r0,#0 @ stop if quotient = 0
subne r2,#1 @ else previous position
bne 1b @ and loop
@ and move digit from left of area
mov r4,#0
2:
ldrb r1,[r3,r2]
strb r1,[r3,r4]
add r2,#1
add r4,#1
cmp r2,#LGZONECAL
ble 2b
@ and move spaces in end on area
mov r0,r4 @ result length
mov r1,#' ' @ space
3:
strb r1,[r3,r4] @ store space in area
add r4,#1 @ next position
cmp r4,#LGZONECAL
ble 3b @ loop if r4 <= area size
100:
pop {r1-r4,lr} @ restaur registres
bx lr @return
/***************************************************/
/* division par 10 unsigned */
/***************************************************/
/* r0 dividende */
/* r0 quotient */
/* r1 remainder */
divisionpar10U:
push {r2,r3,r4, lr}
mov r4,r0 @ save value
//mov r3,#0xCCCD @ r3 <- magic_number lower raspberry 3
//movt r3,#0xCCCC @ r3 <- magic_number higter raspberry 3
ldr r3,iMagicNumber @ r3 <- magic_number raspberry 1 2
umull r1, r2, r3, r0 @ r1<- Lower32Bits(r1*r0) r2<- Upper32Bits(r1*r0)
mov r0, r2, LSR #3 @ r2 <- r2 >> shift 3
add r2,r0,r0, lsl #2 @ r2 <- r0 * 5
sub r1,r4,r2, lsl #1 @ r1 <- r4 - (r2 * 2) = r4 - (r0 * 10)
pop {r2,r3,r4,lr}
bx lr @ leave function
iMagicNumber: .int 0xCCCCCCCD
|
http://rosettacode.org/wiki/Sorting_algorithms/Patience_sort | Sorting algorithms/Patience sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Sort an array of numbers (of any convenient size) into ascending order using Patience sorting.
Related task
Longest increasing subsequence
| #Icon | Icon | #---------------------------------------------------------------------
#
# Patience sorting.
#
procedure patience_sort (less, lst)
local piles
piles := deal (less, lst)
return k_way_merge (less, piles)
end
procedure deal (less, lst)
local piles
local x
local i
piles := []
every x := !lst do {
i := find_pile (less, x, piles)
if i = *piles + 1 then {
# Start a new pile after the existing ones.
put (piles, [x])
} else {
# Push the new value onto the top of an existing pile.
push (piles[i], x)
}
}
return piles
end
procedure find_pile (less, x, piles)
local i, j, k
#
# Do a Bottenbruch search for the leftmost pile whose top is greater
# than or equal to x. Return an index such that:
#
# * if x is greater than the top element at the far right, then
# the index returned will be num-piles.
#
# * otherwise, x is greater than every top element to the left of
# index, and less than or equal to the top elements at index and
# to the right of index.
#
# References:
#
# * H. Bottenbruch, "Structure and use of ALGOL 60", Journal of
# the ACM, Volume 9, Issue 2, April 1962, pp.161-221.
# https://doi.org/10.1145/321119.321120
#
# The general algorithm is described on pages 214 and 215.
#
# * https://en.wikipedia.org/w/index.php?title=Binary_search_algorithm&oldid=1062988272#Alternative_procedure
#
j := 0
k := *piles - 1
until j = k do {
i := (j + k) / 2
if less (piles[j + 1][1], x) then {
j := i + 1
} else {
k := i
}
}
if j = *piles - 1 & less (piles[j + 1][1], x) then {
# We need a new pile.
j +:= 1
}
return j + 1
end
#---------------------------------------------------------------------
#
# k-way merge by tournament tree.
#
# See Knuth, volume 3, and also
# https://en.wikipedia.org/w/index.php?title=K-way_merge_algorithm&oldid=1047851465#Tournament_Tree
#
# However, I store a winners tree instead of the recommended losers
# tree. If the tree were stored as linked nodes, it would probably be
# more efficient to store a losers tree. However, I am storing the
# tree as an Icon list, and one can find an opponent quickly by simply
# toggling the least significant bit of a competitor's array index.
#
record infinity ()
procedure is_infinity (x)
return type (x) == "infinity"
end
procedure k_way_merge (less, lists)
local merged_list
# Return the merge as a list, which is guaranteed to be freshly
# allocated.
every put (merged_list := [], generate_k_way_merge (less, lists))
return merged_list
end
procedure generate_k_way_merge (less, lists)
# Generate the results of the merge.
case *lists of {
0 : fail
1 : every suspend !(lists[1])
default : every suspend generate_merged_lists (less, lists)
}
end
procedure generate_merged_lists (less, lists)
local indices
local winners
local winner, winner_index
local i
local next_value
indices := list (*lists, 2)
winners := build_tree (less, lists)
until is_infinity (winners[1][1]) do {
suspend winners[1][1]
winner_index := winners[1][2]
next_value := get_next (lists, indices, winner_index)
i := ((*winners + 1) / 2) + winner_index - 1
winners[i] := [next_value, winner_index]
replay_games (less, winners, i)
}
end
procedure build_tree (less, lists)
local total_external_nodes
local total_nodes
local winners
local i, j
local istart
local i1, i2
local elem1, elem2
local iwinner, winner
total_external_nodes := next_power_of_two (*lists)
total_nodes := (2 * total_external_nodes) - 1
winners := list (total_nodes)
every i := 1 to total_external_nodes do {
j := total_external_nodes + (i - 1)
if *lists < i | *(lists[i]) = 0 then {
winners[j] := [infinity (), i]
} else {
winners[j] := [lists[i][1], i]
}
}
istart := total_external_nodes
while istart ~= 1 do {
every i := istart to (2 * istart) - 1 by 2 do {
i1 := i
i2 := ixor (i, 1)
elem1 := winners[i1][1]
elem2 := winners[i2][1]
iwinner := (if play_game (less, elem1, elem2) then i1 else i2)
winner := winners[iwinner]
winners[i / 2] := winner
}
istart /:= 2
}
return winners
end
procedure replay_games (less, winners, i)
local i1, i2
local elem1, elem2
local iwinner, winner
until i = 1 do {
i1 := i
i2 := ixor (i1, 1)
elem1 := winners[i1][1]
elem2 := winners[i2][1]
iwinner := (if play_game (less, elem1, elem2) then i1 else i2)
winner := winners[iwinner]
i /:= 2
winners[i] := winner
}
return
end
procedure play_game (less, x, y)
if is_infinity (x) then fail
if is_infinity (y) then return
if less (y, x) then fail
return
end
procedure get_next (lists, indices, i)
local next_value
if *(lists[i]) < indices[i] then {
next_value := infinity ()
} else {
next_value := lists[i][indices[i]]
indices[i] +:= 1
}
return next_value
end
procedure next_power_of_two (n)
local i
# This need not be a fast implementation. Also, it need not return
# any value less than 2; a single list requires no merge.
i := 2
while i < n do i +:= i
return i
end
#---------------------------------------------------------------------
procedure main ()
local example_numbers
example_numbers := [22, 15, 98, 82, 22, 4, 58, 70, 80, 38, 49, 48,
46, 54, 93, 8, 54, 2, 72, 84, 86, 76, 53, 37,
90]
writes ("unsorted ")
every writes (" ", !example_numbers)
write ()
writes ("sorted ")
every writes (" ", !patience_sort ("<", example_numbers))
write ()
end
#--------------------------------------------------------------------- |
http://rosettacode.org/wiki/Sorting_algorithms/Insertion_sort | Sorting algorithms/Insertion sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
This page uses content from Wikipedia. The original article was at Insertion sort. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
An O(n2) sorting algorithm which moves elements one at a time into the correct position.
The algorithm consists of inserting one element at a time into the previously sorted part of the array, moving higher ranked elements up as necessary.
To start off, the first (or smallest, or any arbitrary) element of the unsorted array is considered to be the sorted part.
Although insertion sort is an O(n2) algorithm, its simplicity, low overhead, good locality of reference and efficiency make it a good choice in two cases:
small n,
as the final finishing-off algorithm for O(n logn) algorithms such as mergesort and quicksort.
The algorithm is as follows (from wikipedia):
function insertionSort(array A)
for i from 1 to length[A]-1 do
value := A[i]
j := i-1
while j >= 0 and A[j] > value do
A[j+1] := A[j]
j := j-1
done
A[j+1] = value
done
Writing the algorithm for integers will suffice.
| #Ada | Ada | type Data_Array is array(Natural range <>) of Integer;
procedure Insertion_Sort(Item : in out Data_Array) is
First : Natural := Item'First;
Last : Natural := Item'Last;
Value : Integer;
J : Integer;
begin
for I in (First + 1)..Last loop
Value := Item(I);
J := I - 1;
while J in Item'range and then Item(J) > Value loop
Item(J + 1) := Item(J);
J := J - 1;
end loop;
Item(J + 1) := Value;
end loop;
end Insertion_Sort; |
http://rosettacode.org/wiki/Sorting_algorithms/Permutation_sort | Sorting algorithms/Permutation sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Implement a permutation sort, which proceeds by generating the possible permutations
of the input array/list until discovering the sorted one.
Pseudocode:
while not InOrder(list) do
nextPermutation(list)
done
| #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref symbols nobinary
import java.util.List
import java.util.ArrayList
numeric digits 20
class RSortingPermutationsort public
properties private static
iterations
maxIterations
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method permutationSort(vlist = List) public static returns List
perm = RPermutationIterator(vlist)
iterations = 0
maxIterations = RPermutationIterator.factorial(vlist.size())
loop while perm.hasNext()
iterations = iterations + 1
pl = List perm.next()
if isSorted(pl) then leave
else pl = null
end
return pl
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method isSorted(ss = List) private static returns boolean
status = isTrue
loop ix = 1 while ix < ss.size()
vleft = Rexx ss.get(ix - 1)
vright = Rexx ss.get(ix)
if vleft.datatype('N') & vright.datatype('N')
then vtest = vleft > vright -- For numeric types we must use regular comparison.
else vtest = vleft >> vright -- For non-numeric/mixed types we must do strict comparison.
if vtest then do
status = isFalse
leave ix
end
end ix
return status
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method runSample(arg) private static
placesList = -
"UK London, US New York, US Boston, US Washington" -
"UK Washington, US Birmingham, UK Birmingham, UK Boston"
anotherList = 'Alpha, Beta, Gamma, Beta'
reversed = '7, 6, 5, 4, 3, 2, 1'
unsorted = '734, 3, 1, 24, 324, -1024, -666, -1, 0, 324, 99999999'
lists = [makeList(placesList), makeList(anotherList), makeList(reversed), makeList(unsorted)]
loop il = 0 while il < lists.length
vlist = lists[il]
say vlist
runtime = System.nanoTime()
rlist = permutationSort(vlist)
runtime = System.nanoTime() - runtime
if rlist \= null then say rlist
else say 'sort failed'
say 'This permutation sort of' vlist.size() 'elements took' iterations 'passes (of' maxIterations') to complete. \-'
say 'Elapsed time:' (runtime / 10 ** 9)'s.'
say
end il
return
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method makeList(in) public static returns List
lst = ArrayList()
loop while in > ''
parse in val ',' in
lst.add(val.strip())
end
return lst
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method main(args = String[]) public static
runSample(Rexx(args))
return
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method isTrue() public static returns boolean
return (1 == 1)
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method isFalse() public static returns boolean
return (1 == 0)
|
http://rosettacode.org/wiki/Sorting_algorithms/Pancake_sort | Sorting algorithms/Pancake sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array of integers (of any convenient size) into ascending order using Pancake sorting.
In short, instead of individual elements being sorted, the only operation allowed is to "flip" one end of the list, like so:
Before: 6 7 8 9 2 5 3 4 1
After: 9 8 7 6 2 5 3 4 1
Only one end of the list can be flipped; this should be the low end, but the high end is okay if it's easier to code or works better, but it must be the same end for the entire solution. (The end flipped can't be arbitrarily changed.)
Show both the initial, unsorted list and the final sorted list.
(Intermediate steps during sorting are optional.)
Optimizations are optional (but recommended).
Related tasks
Number reversal game
Topswops
Also see
Wikipedia article: pancake sorting.
| #Euphoria | Euphoria | function flip(sequence s, integer n)
object temp
for i = 1 to n/2 do
temp = s[i]
s[i] = s[n-i+1]
s[n-i+1] = temp
end for
return s
end function
function pancake_sort(sequence s)
integer m
for i = length(s) to 2 by -1 do
m = 1
for j = 2 to i do
if compare(s[j], s[m]) > 0 then
m = j
end if
end for
if m < i then
if m > 1 then
s = flip(s,m)
end if
s = flip(s,i)
end if
end for
return s
end function
constant s = rand(repeat(100,10))
? s
? pancake_sort(s) |
http://rosettacode.org/wiki/Sorting_algorithms/Stooge_sort | Sorting algorithms/Stooge sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
This page uses content from Wikipedia. The original article was at Stooge sort. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Show the Stooge Sort for an array of integers.
The Stooge Sort algorithm is as follows:
algorithm stoogesort(array L, i = 0, j = length(L)-1)
if L[j] < L[i] then
L[i] ↔ L[j]
if j - i > 1 then
t := (j - i + 1)/3
stoogesort(L, i , j-t)
stoogesort(L, i+t, j )
stoogesort(L, i , j-t)
return L
| #MAXScript | MAXScript | fn stoogeSort arr i: j: =
(
if i == unsupplied do i = 1
if j == unsupplied do j = arr.count
if arr[j] < arr[i] do
(
swap arr[j] arr[i]
)
if j - i > 1 do
(
local t = (j - i+1)/3
arr = stoogeSort arr i:i j:(j-t)
arr = stoogeSort arr i:(i+t) j:j
arr = stoogeSort arr i:i j:(j-t)
)
return arr
) |
http://rosettacode.org/wiki/Sorting_algorithms/Stooge_sort | Sorting algorithms/Stooge sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
This page uses content from Wikipedia. The original article was at Stooge sort. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Show the Stooge Sort for an array of integers.
The Stooge Sort algorithm is as follows:
algorithm stoogesort(array L, i = 0, j = length(L)-1)
if L[j] < L[i] then
L[i] ↔ L[j]
if j - i > 1 then
t := (j - i + 1)/3
stoogesort(L, i , j-t)
stoogesort(L, i+t, j )
stoogesort(L, i , j-t)
return L
| #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref savelog symbols binary
iList = [int 1, 4, 5, 3, -6, 3, 7, 10, -2, -5, 7, 5, 9, -3, 7]
sList = Arrays.copyOf(iList, iList.length)
sList = stoogeSort(sList)
lists = [iList, sList]
loop ln = 0 to lists.length - 1
cl = lists[ln]
rpt = Rexx('')
loop ct = 0 to cl.length - 1
rpt = rpt cl[ct]
end ct
say '['rpt.strip().changestr(' ', ',')']'
end ln
return
method stoogeSort(L_ = int[], i_ = 0, j_ = L_.length - 1) public static returns int[]
if L_[j_] < L_[i_] then do
Lt = L_[i_]
L_[i_] = L_[j_]
L_[j_] = Lt
end
if j_ - i_ > 1 then do
t_ = (j_ - i_ + 1) % 3
L_ = stoogeSort(L_, i_, j_ - t_)
L_ = stoogeSort(L_, i_ + t_, j_)
L_ = stoogeSort(L_, i_, j_ - t_)
end
return L_
|
http://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort | Sorting algorithms/Sleep sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
In general, sleep sort works by starting a separate task for each item to be sorted, where each task sleeps for an interval corresponding to the item's sort key, then emits the item. Items are then collected sequentially in time.
Task: Write a program that implements sleep sort. Have it accept non-negative integers on the command line and print the integers in sorted order. If this is not idomatic in your language or environment, input and output may be done differently. Enhancements for optimization, generalization, practicality, robustness, and so on are not required.
Sleep sort was presented anonymously on 4chan and has been discussed on Hacker News.
| #Racket | Racket |
#lang racket
;; accepts a list to sort
(define (sleep-sort lst)
(define done (make-channel))
(for ([elem lst])
(thread
(λ ()
(sleep elem)
(channel-put done elem))))
(for/list ([_ (length lst)])
(channel-get done)))
;; outputs '(2 5 5 7 8 9 10)
(sleep-sort '(5 8 2 7 9 10 5))
|
http://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort | Sorting algorithms/Sleep sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
In general, sleep sort works by starting a separate task for each item to be sorted, where each task sleeps for an interval corresponding to the item's sort key, then emits the item. Items are then collected sequentially in time.
Task: Write a program that implements sleep sort. Have it accept non-negative integers on the command line and print the integers in sorted order. If this is not idomatic in your language or environment, input and output may be done differently. Enhancements for optimization, generalization, practicality, robustness, and so on are not required.
Sleep sort was presented anonymously on 4chan and has been discussed on Hacker News.
| #Raku | Raku | await map -> $delay { start { sleep $delay ; say $delay } },
<6 8 1 12 2 14 5 2 1 0>; |
http://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort | Sorting algorithms/Sleep sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
In general, sleep sort works by starting a separate task for each item to be sorted, where each task sleeps for an interval corresponding to the item's sort key, then emits the item. Items are then collected sequentially in time.
Task: Write a program that implements sleep sort. Have it accept non-negative integers on the command line and print the integers in sorted order. If this is not idomatic in your language or environment, input and output may be done differently. Enhancements for optimization, generalization, practicality, robustness, and so on are not required.
Sleep sort was presented anonymously on 4chan and has been discussed on Hacker News.
| #REXX | REXX | /*REXX program implements a sleep sort (with numbers entered from the command line (CL).*/
numeric digits 300 /*over the top, but what the hey! */
/* (above) ··· from vaudeville. */
@.= /*placeholder for the array of numbers.*/
stuff= 1e9 50 5 40 4 1 100 30 3 12 2 8 9 7 6 6 10 20 0 /*alphabetically ··· so far.*/
parse arg numbers /*obtain optional arguments from the CL*/
if numbers='' then numbers= stuff /*Not specified? Then use the default.*/
N= words(numbers) /*N is the number of numbers in list. */
w= length(N) /*width of N (used for nice output). */
parse upper version !ver . /*obtain which REXX we're running under*/
!regina= ('REXX-REGINA'==left(!ver, 11) ) /*indicate (or not) if this is Regina. */
say N 'numbers to be sorted:' numbers /*informative informational information*/
/*from department of redundancy depart.*/
do j=1 for N /*let's start to boogie─woogie da sort.*/
@.j= word(numbers, j) /*plug in a single number at a time. */
if datatype(@.j, 'N') then @.j= @.j / 1 /*normalize it if it's a numeric number*/
if !regina then call fork /*only REGINA REXX supports FORK BIF.*/
call sortItem j /*start a sort for an array number. */
end /*j*/
do forever while \inOrder(N) /*wait for the sorts to complete. */
call delay 1 /*one second is minimum effective time.*/
end /*forever while*/ /*well heck, other than zero seconds. */
m= max(length(@.1), length(@.N) ) /*width of smallest or largest number. */
say; say 'after sort:' /*display a blank line and a title. */
do k=1 for N /*list the (sorted) array's elements.*/
say left('', 20) 'array element' right(k, w) '───►' right(@.k, m)
end /*k*/
exit /*stick a fork in it, we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
sortItem: procedure expose @.; parse arg ? /*sorts a single (numeric) item. */
do Asort=1 until \switched /*sort unsorted array until it's sorted*/
switched= 0 /*it's all hunky─dorey, happy─dappy ···*/
do i=1 while @.i\=='' & \switched
if @.? >= @.i then iterate /*item is in order. */
parse value @.? @.i with @.i @.?
switched= 1 /* [↑] swapped one.*/
end /*i*/
if Asort//?==0 then call delay switched /*sleep if last item*/
end /*Asort*/
return /*Sleeping Beauty awakes. Not to worry: (c)=circa 1697.*/
/*──────────────────────────────────────────────────────────────────────────────────────*/
inOrder: procedure expose @.; parse arg howMany /*is the array in numerical order? */
do m=1 for howMany-1; next= m+1; if @.m>@.next then return 0 /*¬ in order*/
end /*m*/ /*keep looking for fountain of youth. */
return 1 /*yes, indicate with an indicator. */ |
http://rosettacode.org/wiki/Sorting_algorithms/Selection_sort | Sorting algorithms/Selection sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array (or list) of elements using the Selection sort algorithm.
It works as follows:
First find the smallest element in the array and exchange it with the element in the first position, then find the second smallest element and exchange it with the element in the second position, and continue in this way until the entire array is sorted.
Its asymptotic complexity is O(n2) making it inefficient on large arrays.
Its primary purpose is for when writing data is very expensive (slow) when compared to reading, eg. writing to flash memory or EEPROM.
No other sorting algorithm has less data movement.
References
Rosetta Code: O (complexity).
Wikipedia: Selection sort.
Wikipedia: [Big O notation].
| #Eiffel | Eiffel |
class
SELECTION_SORT [G -> COMPARABLE]
feature {NONE}
index_of_min (ar: ARRAY [G]; lower: INTEGER): INTEGER
--Index of smallest element in 'ar' in the range of lower and the max index.
require
lower_positiv: lower >= 1
lower_in_range: lower <= ar.count
ar_not_void: ar /= Void
local
i: INTEGER
min: G
do
from
i := lower
min := ar.item (i)
Result := i
until
i + 1 > ar.count
loop
if ar.item (i + 1) < min then
min := ar.item (i + 1)
Result := i + 1
end
i := i + 1
end
ensure
result_is_set: Result /= Void
end
sort (ar: ARRAY [G]): ARRAY [G]
-- sort array ar with selectionsort
require
ar_not_void: ar /= Void
local
min_index: INTEGER
ith: G
do
create Result.make_empty
Result.deep_copy (ar)
across
Result as ic
loop
min_index := index_of_min (Result, ic.cursor_index)
ith := Result [ic.cursor_index]
Result [ic.cursor_index] := Result [min_index]
Result [min_index] := ith
end
ensure
Result_is_set: Result /= Void
Result_sorted: is_sorted (Result) = True
end
is_sorted (ar: ARRAY [G]): BOOLEAN
--- Is 'ar' sorted in ascending order?
require
ar_not_empty: ar.is_empty = False
local
i: INTEGER
do
Result := True
from
i := ar.lower
until
i = ar.upper
loop
if ar [i] > ar [i + 1] then
Result := False
end
i := i + 1
end
end
feature
selectionsort (ar: ARRAY [G]): ARRAY [G]
do
Result := sort (ar)
end
end
|
http://rosettacode.org/wiki/Soundex | Soundex | Soundex is an algorithm for creating indices for words based on their pronunciation.
Task
The goal is for homophones to be encoded to the same representation so that they can be matched despite minor differences in spelling (from the soundex Wikipedia article).
Caution
There is a major issue in many of the implementations concerning the separation of two consonants that have the same soundex code! According to the official Rules [[1]]. So check for instance if Ashcraft is coded to A-261.
If a vowel (A, E, I, O, U) separates two consonants that have the same soundex code, the consonant to the right of the vowel is coded. Tymczak is coded as T-522 (T, 5 for the M, 2 for the C, Z ignored (see "Side-by-Side" rule above), 2 for the K). Since the vowel "A" separates the Z and K, the K is coded.
If "H" or "W" separate two consonants that have the same soundex code, the consonant to the right of the vowel is not coded. Example: Ashcraft is coded A-261 (A, 2 for the S, C ignored, 6 for the R, 1 for the F). It is not coded A-226.
| #Factor | Factor | USE: soundex
"soundex" soundex ! S532
"example" soundex ! E251
"ciondecks" soundex ! C532
"ekzampul" soundex ! E251 |
http://rosettacode.org/wiki/Sorting_algorithms/Shell_sort | Sorting algorithms/Shell sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array of elements using the Shell sort algorithm, a diminishing increment sort.
The Shell sort (also known as Shellsort or Shell's method) is named after its inventor, Donald Shell, who published the algorithm in 1959.
Shell sort is a sequence of interleaved insertion sorts based on an increment sequence.
The increment size is reduced after each pass until the increment size is 1.
With an increment size of 1, the sort is a basic insertion sort, but by this time the data is guaranteed to be almost sorted, which is insertion sort's "best case".
Any sequence will sort the data as long as it ends in 1, but some work better than others.
Empirical studies have shown a geometric increment sequence with a ratio of about 2.2 work well in practice.
[1]
Other good sequences are found at the On-Line Encyclopedia of Integer Sequences.
| #jq | jq | # The "while" loops are implemented using the following jq function:
# As soon as "condition" is true, then emit . and stop:
def do_until(condition; next):
def u: if condition then . else (next|u) end;
u;
# sort the input array
def shellSort:
length as $length
| [ ($length/2|floor), .] # L1: state: [h, array]
| do_until( .[0] == 0;
.[0] as $h
| reduce range($h; $length) as $i # L2: state: array
( .[1];
.[$i] as $k
| [ $i, . ] # L3: state: [j, array]
| do_until( .[0] < $h or ($k >= .[1][.[0] - $h]);
.[0] as $j
| [ ($j - $h), (.[1]|setpath([$j]; .[$j - $h])) ] )
| .[0] as $j | (.[1]|setpath([$j]; $k)) # i.e. a[j] = $k
)
| [(($h+1)*5/11 | floor), .] )
| .[1] ; |
http://rosettacode.org/wiki/Sorting_algorithms/Shell_sort | Sorting algorithms/Shell sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array of elements using the Shell sort algorithm, a diminishing increment sort.
The Shell sort (also known as Shellsort or Shell's method) is named after its inventor, Donald Shell, who published the algorithm in 1959.
Shell sort is a sequence of interleaved insertion sorts based on an increment sequence.
The increment size is reduced after each pass until the increment size is 1.
With an increment size of 1, the sort is a basic insertion sort, but by this time the data is guaranteed to be almost sorted, which is insertion sort's "best case".
Any sequence will sort the data as long as it ends in 1, but some work better than others.
Empirical studies have shown a geometric increment sequence with a ratio of about 2.2 work well in practice.
[1]
Other good sequences are found at the On-Line Encyclopedia of Integer Sequences.
| #Julia | Julia | # v0.6
function shellsort!(a::Array{Int})::Array{Int}
incr = div(length(a), 2)
while incr > 0
for i in incr+1:length(a)
j = i
tmp = a[i]
while j > incr && a[j - incr] > tmp
a[j] = a[j-incr]
j -= incr
end
a[j] = tmp
end
if incr == 2
incr = 1
else
incr = floor(Int, incr * 5.0 / 11)
end
end
return a
end
x = rand(1:10, 10)
@show x shellsort!(x)
@assert issorted(x) |
http://rosettacode.org/wiki/Stable_marriage_problem | Stable marriage problem | Solve the Stable marriage problem using the Gale/Shapley algorithm.
Problem description
Given an equal number of men and women to be paired for marriage, each man ranks all the women in order of his preference and each woman ranks all the men in order of her preference.
A stable set of engagements for marriage is one where no man prefers a woman over the one he is engaged to, where that other woman also prefers that man over the one she is engaged to. I.e. with consulting marriages, there would be no reason for the engagements between the people to change.
Gale and Shapley proved that there is a stable set of engagements for any set of preferences and the first link above gives their algorithm for finding a set of stable engagements.
Task Specifics
Given ten males:
abe, bob, col, dan, ed, fred, gav, hal, ian, jon
And ten females:
abi, bea, cath, dee, eve, fay, gay, hope, ivy, jan
And a complete list of ranked preferences, where the most liked is to the left:
abe: abi, eve, cath, ivy, jan, dee, fay, bea, hope, gay
bob: cath, hope, abi, dee, eve, fay, bea, jan, ivy, gay
col: hope, eve, abi, dee, bea, fay, ivy, gay, cath, jan
dan: ivy, fay, dee, gay, hope, eve, jan, bea, cath, abi
ed: jan, dee, bea, cath, fay, eve, abi, ivy, hope, gay
fred: bea, abi, dee, gay, eve, ivy, cath, jan, hope, fay
gav: gay, eve, ivy, bea, cath, abi, dee, hope, jan, fay
hal: abi, eve, hope, fay, ivy, cath, jan, bea, gay, dee
ian: hope, cath, dee, gay, bea, abi, fay, ivy, jan, eve
jon: abi, fay, jan, gay, eve, bea, dee, cath, ivy, hope
abi: bob, fred, jon, gav, ian, abe, dan, ed, col, hal
bea: bob, abe, col, fred, gav, dan, ian, ed, jon, hal
cath: fred, bob, ed, gav, hal, col, ian, abe, dan, jon
dee: fred, jon, col, abe, ian, hal, gav, dan, bob, ed
eve: jon, hal, fred, dan, abe, gav, col, ed, ian, bob
fay: bob, abe, ed, ian, jon, dan, fred, gav, col, hal
gay: jon, gav, hal, fred, bob, abe, col, ed, dan, ian
hope: gav, jon, bob, abe, ian, dan, hal, ed, col, fred
ivy: ian, col, hal, gav, fred, bob, abe, ed, jon, dan
jan: ed, hal, gav, abe, bob, jon, col, ian, fred, dan
Use the Gale Shapley algorithm to find a stable set of engagements
Perturb this set of engagements to form an unstable set of engagements then check this new set for stability.
References
The Stable Marriage Problem. (Eloquent description and background information).
Gale-Shapley Algorithm Demonstration.
Another Gale-Shapley Algorithm Demonstration.
Stable Marriage Problem - Numberphile (Video).
Stable Marriage Problem (the math bit) (Video).
The Stable Marriage Problem and School Choice. (Excellent exposition)
| #Ursala | Ursala | men =
{
'abe': <'abi','eve','cath','ivy','jan','dee','fay','bea','hope','gay'>,
'bob': <'cath','hope','abi','dee','eve','fay','bea','jan','ivy','gay'>,
'col': <'hope','eve','abi','dee','bea','fay','ivy','gay','cath','jan'>,
'dan': <'ivy','fay','dee','gay','hope','eve','jan','bea','cath','abi'>,
'ed': <'jan','dee','bea','cath','fay','eve','abi','ivy','hope','gay'>,
'fred': <'bea','abi','dee','gay','eve','ivy','cath','jan','hope','fay'>,
'gav': <'gay','eve','ivy','bea','cath','abi','dee','hope','jan','fay'>,
'hal': <'abi','eve','hope','fay','ivy','cath','jan','bea','gay','dee'>,
'ian': <'hope','cath','dee','gay','bea','abi','fay','ivy','jan','eve'>,
'jon': <'abi','fay','jan','gay','eve','bea','dee','cath','ivy','hope'>}
women =
{
'abi': <'bob','fred','jon','gav','ian','abe','dan','ed','col','hal'>,
'bea': <'bob','abe','col','fred','gav','dan','ian','ed','jon','hal'>,
'cath': <'fred','bob','ed','gav','hal','col','ian','abe','dan','jon'>,
'dee': <'fred','jon','col','abe','ian','hal','gav','dan','bob','ed'>,
'eve': <'jon','hal','fred','dan','abe','gav','col','ed','ian','bob'>,
'fay': <'bob','abe','ed','ian','jon','dan','fred','gav','col','hal'>,
'gay': <'jon','gav','hal','fred','bob','abe','col','ed','dan','ian'>,
'hope': <'gav','jon','bob','abe','ian','dan','hal','ed','col','fred'>,
'ivy': <'ian','col','hal','gav','fred','bob','abe','ed','jon','dan'>,
'jan': <'ed','hal','gav','abe','bob','jon','col','ian','fred','dan'>}
match = # finds a stable list of engagements from data as given above
-+
^=rrmhPnXS ^/~&l ^/~&rl ^|DlrHSs/~& ^TlK2hlPrSLPAS\~&r -+
~&lK2hlPrSXS,
*=rnmihBPK12D ~&mmhPnXNCB^rnPrmPllSPcA\~&r ~&lrrPwZK17@rnPlX+-,
^|rrPlrlPXX/~& ^/~&nNAS ^/~&l+ ^|H\~&+ -:+ * ^|/~& -<+ \/-=+ ~&DSL@tK33+-
preferred = # finds non-couples that would prefer each other to their betrothed
~&lSLPrSLrlXS2c^|DlrHS\~& ~~irlXX+ ^D/~&l+ ^|H\~&+ -:+ *T ^|/~& //~=;+ -~l;+ \/~&H
#cast %sWLm
main = # stable, perturbed, and preferred alternatives to the perturbed
<
'stable': match/men women,
'perturbed': ~&lSrSxPp match/men women,
'preferred': preferred/(men,women) ~&lSrSxPp match/men women> |
http://rosettacode.org/wiki/Stack | Stack |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also called LIFO.
The stack is accessed through its top.
The basic stack operations are:
push stores a new element onto the stack top;
pop returns the last pushed stack element, while removing it from the stack;
empty tests if the stack contains no elements.
Sometimes the last pushed stack element is made accessible for immutable access (for read) or mutable access (for write):
top (sometimes called peek to keep with the p theme) returns the topmost element without modifying the stack.
Stacks allow a very simple hardware implementation.
They are common in almost all processors.
In programming, stacks are also very popular for their way (LIFO) of resource management, usually memory.
Nested scopes of language objects are naturally implemented by a stack (sometimes by multiple stacks).
This is a classical way to implement local variables of a re-entrant or recursive subprogram. Stacks are also used to describe a formal computational framework.
See stack machine.
Many algorithms in pattern matching, compiler construction (e.g. recursive descent parsers), and machine learning (e.g. based on tree traversal) have a natural representation in terms of stacks.
Task
Create a stack supporting the basic operations: push, pop, empty.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
| #Logo | Logo | make "stack []
push "stack 1
push "stack 2
push "stack 3
print pop "stack ; 3
print empty? :stack ; false |
http://rosettacode.org/wiki/Spiral_matrix | Spiral matrix | Task
Produce a spiral array.
A spiral array is a square arrangement of the first N2 natural numbers, where the
numbers increase sequentially as you go around the edges of the array spiraling inwards.
For example, given 5, produce this array:
0 1 2 3 4
15 16 17 18 5
14 23 24 19 6
13 22 21 20 7
12 11 10 9 8
Related tasks
Zig-zag matrix
Identity_matrix
Ulam_spiral_(for_primes)
| #Maxima | Maxima | spiral(n) := block([a, i, j, k, p, di, dj, vi, vj, imin, imax, jmin, jmax],
a: zeromatrix(n, n),
vi: [1, 0, -1, 0],
vj: [0, 1, 0, -1],
imin: 0,
imax: n,
jmin: 1,
jmax: n + 1,
p: 1,
di: vi[p],
dj: vj[p],
i: 1,
j: 1,
for k from 1 thru n*n do (
a[j, i]: k,
i: i + di,
j: j + dj,
if i < imin or i > imax or j < jmin or j > jmax then (
i: i - di,
j: j - dj,
p: mod(p, 4) + 1,
di: vi[p],
dj: vj[p],
i: i + di,
j: j + dj,
if p = 1 then imax: imax - 1
elseif p = 2 then jmax: jmax - 1
elseif p = 3 then imin: imin + 1
else jmin: jmin + 1
)
),
a
)$
spiral(5);
/* matrix([ 1, 2, 3, 4, 5],
[16, 17, 18, 19, 6],
[15, 24, 25, 20, 7],
[14, 23, 22, 21, 8],
[13, 12, 11, 10, 9]) */ |
http://rosettacode.org/wiki/Sorting_algorithms/Radix_sort | Sorting algorithms/Radix sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an integer array with the radix sort algorithm.
The primary purpose is to complete the characterization of sort algorithms task.
| #Kotlin | Kotlin | // version 1.1.2
fun radixSort(original: IntArray): IntArray {
var old = original // Need this to be mutable
// Loop for every bit in the integers
for (shift in 31 downTo 0) {
val tmp = IntArray(old.size) // The array to put the partially sorted array into
var j = 0 // The number of 0s
// Move the 0s to the new array, and the 1s to the old one
for (i in 0 until old.size) {
// If there is a 1 in the bit we are testing, the number will be negative
val move = (old[i] shl shift) >= 0
// If this is the last bit, negative numbers are actually lower
val toBeMoved = if (shift == 0) !move else move
if (toBeMoved)
tmp[j++] = old[i]
else {
// It's a 1, so stick it in the old array for now
old[i - j] = old[i]
}
}
// Copy over the 1s from the old array
for (i in j until tmp.size) tmp[i] = old[i - j]
// And now the tmp array gets switched for another round of sorting
old = tmp
}
return old
}
fun main(args: Array<String>) {
val arrays = arrayOf(
intArrayOf(170, 45, 75, -90, -802, 24, 2, 66),
intArrayOf(-4, 5, -26, 58, -990, 331, 331, 990, -1837, 2028)
)
for (array in arrays) println(radixSort(array).contentToString())
} |
http://rosettacode.org/wiki/Sorting_algorithms/Quicksort | Sorting algorithms/Quicksort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
This page uses content from Wikipedia. The original article was at Quicksort. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Sort an array (or list) elements using the quicksort algorithm.
The elements must have a strict weak order and the index of the array can be of any discrete type.
For languages where this is not possible, sort an array of integers.
Quicksort, also known as partition-exchange sort, uses these steps.
Choose any element of the array to be the pivot.
Divide all other elements (except the pivot) into two partitions.
All elements less than the pivot must be in the first partition.
All elements greater than the pivot must be in the second partition.
Use recursion to sort both partitions.
Join the first sorted partition, the pivot, and the second sorted partition.
The best pivot creates partitions of equal length (or lengths differing by 1).
The worst pivot creates an empty partition (for example, if the pivot is the first or last element of a sorted array).
The run-time of Quicksort ranges from O(n log n) with the best pivots, to O(n2) with the worst pivots, where n is the number of elements in the array.
This is a simple quicksort algorithm, adapted from Wikipedia.
function quicksort(array)
less, equal, greater := three empty arrays
if length(array) > 1
pivot := select any element of array
for each x in array
if x < pivot then add x to less
if x = pivot then add x to equal
if x > pivot then add x to greater
quicksort(less)
quicksort(greater)
array := concatenate(less, equal, greater)
A better quicksort algorithm works in place, by swapping elements within the array, to avoid the memory allocation of more arrays.
function quicksort(array)
if length(array) > 1
pivot := select any element of array
left := first index of array
right := last index of array
while left ≤ right
while array[left] < pivot
left := left + 1
while array[right] > pivot
right := right - 1
if left ≤ right
swap array[left] with array[right]
left := left + 1
right := right - 1
quicksort(array from first index to right)
quicksort(array from left to last index)
Quicksort has a reputation as the fastest sort. Optimized variants of quicksort are common features of many languages and libraries. One often contrasts quicksort with merge sort, because both sorts have an average time of O(n log n).
"On average, mergesort does fewer comparisons than quicksort, so it may be better when complicated comparison routines are used. Mergesort also takes advantage of pre-existing order, so it would be favored for using sort() to merge several sorted arrays. On the other hand, quicksort is often faster for small arrays, and on arrays of a few distinct values, repeated many times." — http://perldoc.perl.org/sort.html
Quicksort is at one end of the spectrum of divide-and-conquer algorithms, with merge sort at the opposite end.
Quicksort is a conquer-then-divide algorithm, which does most of the work during the partitioning and the recursive calls. The subsequent reassembly of the sorted partitions involves trivial effort.
Merge sort is a divide-then-conquer algorithm. The partioning happens in a trivial way, by splitting the input array in half. Most of the work happens during the recursive calls and the merge phase.
With quicksort, every element in the first partition is less than or equal to every element in the second partition. Therefore, the merge phase of quicksort is so trivial that it needs no mention!
This task has not specified whether to allocate new arrays, or sort in place. This task also has not specified how to choose the pivot element. (Common ways to are to choose the first element, the middle element, or the median of three elements.) Thus there is a variety among the following implementations.
| #Arturo | Arturo | quickSort: function [items][
if 2 > size items -> return items
pivot: first items
left: select slice items 1 (size items)-1 'x -> x < pivot
right: select slice items 1 (size items)-1 'x -> x >= pivot
((quickSort left) ++ pivot) ++ quickSort right
]
print quickSort [3 1 2 8 5 7 9 4 6] |
http://rosettacode.org/wiki/Sorting_algorithms/Patience_sort | Sorting algorithms/Patience sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Sort an array of numbers (of any convenient size) into ascending order using Patience sorting.
Related task
Longest increasing subsequence
| #J | J |
Until =: 2 :'u^:(0=v)^:_'
Filter =: (#~`)(`:6)
locate_for_append =: 1 i.~ (<&> {:S:0) NB. returns an index
append =: (<@:(({::~ >:) , 0 {:: [)`]`(}.@:[)}) :: [
pile =: (, append locate_for_append)/@:(;/) NB. pile DATA
smallest =: ((>:@:i. , ]) <./)@:({:S:0@:}.) NB. index of pile with smallest value , that value
transfer =: (}:&.>@:({~ {.) , <@:((0{::[),{:@:]))`(1 0 * ])`[}
unpile =: >@:{.@:((0<#S:0)Filter@:(transfer smallest)Until(1=#))@:(a:&,)
patience_sort =: unpile@:pile
assert (/:~ -: patience_sort) ?@$~30 NB. test with 30 randomly chosen integers
Show =: 1 : 0
smoutput y
u y
:
smoutput A=:x ,&:< y
x u y
)
pile_demo =: (, append Show locate_for_append)/@:(;/) NB. pile DATA
unpile_demo =: >@:{.@:((0<#S:0)Filter@:(transfer Show smallest)Until(1=#))@:(a:&,)
patience_sort_demo =: unpile_demo@:pile_demo
|
http://rosettacode.org/wiki/Sorting_algorithms/Insertion_sort | Sorting algorithms/Insertion sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
This page uses content from Wikipedia. The original article was at Insertion sort. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
An O(n2) sorting algorithm which moves elements one at a time into the correct position.
The algorithm consists of inserting one element at a time into the previously sorted part of the array, moving higher ranked elements up as necessary.
To start off, the first (or smallest, or any arbitrary) element of the unsorted array is considered to be the sorted part.
Although insertion sort is an O(n2) algorithm, its simplicity, low overhead, good locality of reference and efficiency make it a good choice in two cases:
small n,
as the final finishing-off algorithm for O(n logn) algorithms such as mergesort and quicksort.
The algorithm is as follows (from wikipedia):
function insertionSort(array A)
for i from 1 to length[A]-1 do
value := A[i]
j := i-1
while j >= 0 and A[j] > value do
A[j+1] := A[j]
j := j-1
done
A[j+1] = value
done
Writing the algorithm for integers will suffice.
| #ALGOL_68 | ALGOL 68 | MODE DATA = REF CHAR;
PROC in place insertion sort = (REF[]DATA item)VOID:
BEGIN
INT first := LWB item;
INT last := UPB item;
INT j;
DATA value;
FOR i FROM first + 1 TO last DO
value := item[i];
j := i - 1;
# WHILE j >= LWB item AND j <= UPB item ANDF item[j] > value DO // example of ANDF extension #
WHILE ( j >= LWB item AND j <= UPB item | item[j]>value | FALSE ) DO # no extension! #
item[j + 1] := item[j];
j -:= 1
OD;
item[j + 1] := value
OD
END # in place insertion sort #;
[32]CHAR data := "big fjords vex quick waltz nymph";
[UPB data]DATA ref data; FOR i TO UPB data DO ref data[i] := data[i] OD;
in place insertion sort(ref data);
FOR i TO UPB ref data DO print(ref data[i]) OD; print(new line);
print((data)) |
http://rosettacode.org/wiki/Sorting_algorithms/Permutation_sort | Sorting algorithms/Permutation sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Implement a permutation sort, which proceeds by generating the possible permutations
of the input array/list until discovering the sorted one.
Pseudocode:
while not InOrder(list) do
nextPermutation(list)
done
| #Nim | Nim | iterator permutations[T](ys: openarray[T]): seq[T] =
var
d = 1
c = newSeq[int](ys.len)
xs = newSeq[T](ys.len)
for i, y in ys: xs[i] = y
yield xs
block outter:
while true:
while d > 1:
dec d
c[d] = 0
while c[d] >= d:
inc d
if d >= ys.len: break outter
let i = if (d and 1) == 1: c[d] else: 0
swap xs[i], xs[d]
yield xs
inc c[d]
proc isSorted[T](s: openarray[T]): bool =
var last = low(T)
for c in s:
if c < last:
return false
last = c
return true
proc permSort[T](a: openarray[T]): seq[T] =
for p in a.permutations:
if p.isSorted:
return p
var a = @[4, 65, 2, -31, 0, 99, 2, 83, 782]
echo a.permSort |
http://rosettacode.org/wiki/Sorting_algorithms/Permutation_sort | Sorting algorithms/Permutation sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Implement a permutation sort, which proceeds by generating the possible permutations
of the input array/list until discovering the sorted one.
Pseudocode:
while not InOrder(list) do
nextPermutation(list)
done
| #OCaml | OCaml | let rec sorted = function
| e1 :: e2 :: r -> e1 <= e2 && sorted (e2 :: r)
| _ -> true
let rec insert e = function
| [] -> [[e]]
| h :: t as l -> (e :: l) :: List.map (fun t' -> h :: t') (insert e t)
let permute xs = List.fold_right (fun h z -> List.concat (List.map (insert h) z))
xs [[]]
let permutation_sort l = List.find sorted (permute l) |
http://rosettacode.org/wiki/Sorting_algorithms/Pancake_sort | Sorting algorithms/Pancake sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array of integers (of any convenient size) into ascending order using Pancake sorting.
In short, instead of individual elements being sorted, the only operation allowed is to "flip" one end of the list, like so:
Before: 6 7 8 9 2 5 3 4 1
After: 9 8 7 6 2 5 3 4 1
Only one end of the list can be flipped; this should be the low end, but the high end is okay if it's easier to code or works better, but it must be the same end for the entire solution. (The end flipped can't be arbitrarily changed.)
Show both the initial, unsorted list and the final sorted list.
(Intermediate steps during sorting are optional.)
Optimizations are optional (but recommended).
Related tasks
Number reversal game
Topswops
Also see
Wikipedia article: pancake sorting.
| #F.23 | F# | open System
let show data = data |> Array.iter (printf "%d ") ; printfn ""
let split (data: int[]) pos = data.[0..pos], data.[(pos+1)..]
let flip items pos =
let lower, upper = split items pos
Array.append (Array.rev lower) upper
let pancakeSort items =
let rec loop data limit =
if limit <= 0 then data
else
let lower, upper = split data limit
let indexOfMax = lower |> Array.findIndex ((=) (Array.max lower))
let partialSort = Array.append (flip lower indexOfMax |> Array.rev) upper
loop partialSort (limit-1)
loop items ((Array.length items)-1) |
http://rosettacode.org/wiki/Sorting_algorithms/Stooge_sort | Sorting algorithms/Stooge sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
This page uses content from Wikipedia. The original article was at Stooge sort. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Show the Stooge Sort for an array of integers.
The Stooge Sort algorithm is as follows:
algorithm stoogesort(array L, i = 0, j = length(L)-1)
if L[j] < L[i] then
L[i] ↔ L[j]
if j - i > 1 then
t := (j - i + 1)/3
stoogesort(L, i , j-t)
stoogesort(L, i+t, j )
stoogesort(L, i , j-t)
return L
| #Nim | Nim | proc stoogeSort[T](a: var openarray[T], i, j: int) =
if a[j] < a[i]: swap a[i], a[j]
if j - i > 1:
let t = (j - i + 1) div 3
stoogeSort(a, i, j - t)
stoogeSort(a, i + t, j)
stoogeSort(a, i, j - t)
var a = @[4, 65, 2, -31, 0, 99, 2, 83, 782]
stoogeSort a, 0, a.high
echo a |
http://rosettacode.org/wiki/Sorting_algorithms/Stooge_sort | Sorting algorithms/Stooge sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
This page uses content from Wikipedia. The original article was at Stooge sort. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Show the Stooge Sort for an array of integers.
The Stooge Sort algorithm is as follows:
algorithm stoogesort(array L, i = 0, j = length(L)-1)
if L[j] < L[i] then
L[i] ↔ L[j]
if j - i > 1 then
t := (j - i + 1)/3
stoogesort(L, i , j-t)
stoogesort(L, i+t, j )
stoogesort(L, i , j-t)
return L
| #Objeck | Objeck |
bundle Default {
class Stooge {
function : Main(args : String[]) ~ Nil {
nums := [1, 4, 5, 3, -6, 3, 7, 10, -2, -5];
StoogeSort(nums);
each(i : nums) {
IO.Console->Print(nums[i])->Print(",");
};
IO.Console->PrintLine();
}
function : native : StoogeSort(l : Int[]) ~ Nil {
StoogeSort(l, 0, l->Size() - 1);
}
function : native : StoogeSort(l : Int[], i : Int, j : Int) ~ Nil {
if(l[j] < l[i]) {
tmp := l[i];
l[i] := l[j];
l[j] := tmp;
};
if(j - i > 1) {
t := (j - i + 1) / 3;
StoogeSort(l, i, j - t);
StoogeSort(l, i + t, j);
StoogeSort(l, i, j - t);
};
}
}
}
|
http://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort | Sorting algorithms/Sleep sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
In general, sleep sort works by starting a separate task for each item to be sorted, where each task sleeps for an interval corresponding to the item's sort key, then emits the item. Items are then collected sequentially in time.
Task: Write a program that implements sleep sort. Have it accept non-negative integers on the command line and print the integers in sorted order. If this is not idomatic in your language or environment, input and output may be done differently. Enhancements for optimization, generalization, practicality, robustness, and so on are not required.
Sleep sort was presented anonymously on 4chan and has been discussed on Hacker News.
| #Ruby | Ruby | require 'thread'
nums = ARGV.collect(&:to_i)
sorted = []
mutex = Mutex.new
threads = nums.collect do |n|
Thread.new do
sleep 0.01 * n
mutex.synchronize {sorted << n}
end
end
threads.each {|t| t.join}
p sorted |
http://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort | Sorting algorithms/Sleep sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
In general, sleep sort works by starting a separate task for each item to be sorted, where each task sleeps for an interval corresponding to the item's sort key, then emits the item. Items are then collected sequentially in time.
Task: Write a program that implements sleep sort. Have it accept non-negative integers on the command line and print the integers in sorted order. If this is not idomatic in your language or environment, input and output may be done differently. Enhancements for optimization, generalization, practicality, robustness, and so on are not required.
Sleep sort was presented anonymously on 4chan and has been discussed on Hacker News.
| #Rust | Rust | use std::thread;
fn sleepsort<I: Iterator<Item=u32>>(nums: I) {
let threads: Vec<_> = nums.map(|n|
thread::spawn(move || {
thread::sleep_ms(n);
println!("{}", n); })).collect();
for t in threads { t.join(); }
}
fn main() {
sleepsort(std::env::args().skip(1).map(|s| s.parse().unwrap()));
} |
http://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort | Sorting algorithms/Sleep sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
In general, sleep sort works by starting a separate task for each item to be sorted, where each task sleeps for an interval corresponding to the item's sort key, then emits the item. Items are then collected sequentially in time.
Task: Write a program that implements sleep sort. Have it accept non-negative integers on the command line and print the integers in sorted order. If this is not idomatic in your language or environment, input and output may be done differently. Enhancements for optimization, generalization, practicality, robustness, and so on are not required.
Sleep sort was presented anonymously on 4chan and has been discussed on Hacker News.
| #Scala | Scala | object SleepSort {
def main(args: Array[String]): Unit = {
val nums = args.map(_.toInt)
sort(nums)
Thread.sleep(nums.max * 21) // Keep the JVM alive for the example
}
def sort(nums: Seq[Int]): Unit =
nums.foreach(i => new Thread {
override def run() {
Thread.sleep(i * 20) // just `i` is unpredictable with small numbers
print(s"$i ")
}
}.start())
} |
http://rosettacode.org/wiki/Sorting_algorithms/Selection_sort | Sorting algorithms/Selection sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array (or list) of elements using the Selection sort algorithm.
It works as follows:
First find the smallest element in the array and exchange it with the element in the first position, then find the second smallest element and exchange it with the element in the second position, and continue in this way until the entire array is sorted.
Its asymptotic complexity is O(n2) making it inefficient on large arrays.
Its primary purpose is for when writing data is very expensive (slow) when compared to reading, eg. writing to flash memory or EEPROM.
No other sorting algorithm has less data movement.
References
Rosetta Code: O (complexity).
Wikipedia: Selection sort.
Wikipedia: [Big O notation].
| #Elena | Elena | import extensions;
import system'routines;
extension op
{
selectionSort()
{
var copy := self.clone();
for(int i := 0, i < copy.Length, i += 1)
{
int k := i;
for(int j := i + 1, j < copy.Length, j += 1)
{
if (copy[j] < copy[k])
{
k := j
}
};
copy.exchange(i,k)
};
^ copy
}
}
public program()
{
var list := new string[]{"this", "is", "a", "test", "of", "generic", "selection", "sort"};
console.printLine("before:",list.asEnumerable());
console.printLine("after:",list.selectionSort().asEnumerable())
} |
http://rosettacode.org/wiki/Sorting_algorithms/Selection_sort | Sorting algorithms/Selection sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array (or list) of elements using the Selection sort algorithm.
It works as follows:
First find the smallest element in the array and exchange it with the element in the first position, then find the second smallest element and exchange it with the element in the second position, and continue in this way until the entire array is sorted.
Its asymptotic complexity is O(n2) making it inefficient on large arrays.
Its primary purpose is for when writing data is very expensive (slow) when compared to reading, eg. writing to flash memory or EEPROM.
No other sorting algorithm has less data movement.
References
Rosetta Code: O (complexity).
Wikipedia: Selection sort.
Wikipedia: [Big O notation].
| #Elixir | Elixir | defmodule Sort do
def selection_sort(list) when is_list(list), do: selection_sort(list, [])
defp selection_sort([], sorted), do: sorted
defp selection_sort(list, sorted) do
max = Enum.max(list)
selection_sort(List.delete(list, max), [max | sorted])
end
end |
http://rosettacode.org/wiki/Soundex | Soundex | Soundex is an algorithm for creating indices for words based on their pronunciation.
Task
The goal is for homophones to be encoded to the same representation so that they can be matched despite minor differences in spelling (from the soundex Wikipedia article).
Caution
There is a major issue in many of the implementations concerning the separation of two consonants that have the same soundex code! According to the official Rules [[1]]. So check for instance if Ashcraft is coded to A-261.
If a vowel (A, E, I, O, U) separates two consonants that have the same soundex code, the consonant to the right of the vowel is coded. Tymczak is coded as T-522 (T, 5 for the M, 2 for the C, Z ignored (see "Side-by-Side" rule above), 2 for the K). Since the vowel "A" separates the Z and K, the K is coded.
If "H" or "W" separate two consonants that have the same soundex code, the consonant to the right of the vowel is not coded. Example: Ashcraft is coded A-261 (A, 2 for the S, C ignored, 6 for the R, 1 for the F). It is not coded A-226.
| #Forth | Forth | : alpha-table create does> swap 32 or [char] a - 0 max 26 min + 1+ c@ ;
alpha-table soundex-code
," 123 12. 22455 12623 1.2 2 "
\ ABCDEFGHIJKLMNOPQRSTUVWXYZ
: soundex ( name len -- pad len )
over c@ pad c! \ First character verbatim
pad 1+ 3 [char] 0 fill \ Pad to four characters with zeros
1 pad c@ soundex-code ( count code )
2swap bounds do
i c@ soundex-code ( count code next )
2dup = if drop else \ runs are ignored
dup [char] . = if drop else \ W, H don't separate runs of consonants
dup bl = if nip else \ vowels separate consonants but aren't coded
nip
2dup swap pad + c!
swap 1+
tuck 4 = if leave then
then then then
loop
2drop pad 4 ;
\ Knuth's test cases
s" Euler" soundex cr type \ E460
s" Gauss" soundex cr type \ G200
s" Hilbert" soundex cr type \ H416
s" Knuth" soundex cr type \ K530
s" Lloyd" soundex cr type \ L300
s" Lukasiewicz" soundex cr type \ L222 (W test)
s" Ellery" soundex cr type \ E460
s" Ghosh" soundex cr type \ G200
s" Heilbronn" soundex cr type \ H416
s" Kant" soundex cr type \ K530
s" Ladd" soundex cr type \ L300
s" Lissajous" soundex cr type \ L222
s" Wheaton" soundex cr type \ W350
s" Ashcraft" soundex cr type \ A261 (H tests)
s" Burroughs" soundex cr type \ B620
s" Burrows" soundex cr type \ B620 (W test) (any Welsh names?)
s" O'Hara" soundex cr type \ O600 (punctuation test) |
http://rosettacode.org/wiki/Sorting_algorithms/Shell_sort | Sorting algorithms/Shell sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array of elements using the Shell sort algorithm, a diminishing increment sort.
The Shell sort (also known as Shellsort or Shell's method) is named after its inventor, Donald Shell, who published the algorithm in 1959.
Shell sort is a sequence of interleaved insertion sorts based on an increment sequence.
The increment size is reduced after each pass until the increment size is 1.
With an increment size of 1, the sort is a basic insertion sort, but by this time the data is guaranteed to be almost sorted, which is insertion sort's "best case".
Any sequence will sort the data as long as it ends in 1, but some work better than others.
Empirical studies have shown a geometric increment sequence with a ratio of about 2.2 work well in practice.
[1]
Other good sequences are found at the On-Line Encyclopedia of Integer Sequences.
| #Kotlin | Kotlin | // version 1.1.0
val gaps = listOf(701, 301, 132, 57, 23, 10, 4, 1) // Marcin Ciura's gap sequence
fun shellSort(a: IntArray) {
for (gap in gaps) {
for (i in gap until a.size) {
val temp = a[i]
var j = i
while (j >= gap && a[j - gap] > temp) {
a[j] = a[j - gap]
j -= gap
}
a[j] = temp
}
}
}
fun main(args: Array<String>) {
val aa = arrayOf(
intArrayOf(100, 2, 56, 200, -52, 3, 99, 33, 177, -199),
intArrayOf(4, 65, 2, -31, 0, 99, 2, 83, 782, 1),
intArrayOf(62, 83, 18, 53, 7, 17, 95, 86, 47, 69, 25, 28)
)
for (a in aa) {
shellSort(a)
println(a.joinToString(", "))
}
} |
http://rosettacode.org/wiki/Stable_marriage_problem | Stable marriage problem | Solve the Stable marriage problem using the Gale/Shapley algorithm.
Problem description
Given an equal number of men and women to be paired for marriage, each man ranks all the women in order of his preference and each woman ranks all the men in order of her preference.
A stable set of engagements for marriage is one where no man prefers a woman over the one he is engaged to, where that other woman also prefers that man over the one she is engaged to. I.e. with consulting marriages, there would be no reason for the engagements between the people to change.
Gale and Shapley proved that there is a stable set of engagements for any set of preferences and the first link above gives their algorithm for finding a set of stable engagements.
Task Specifics
Given ten males:
abe, bob, col, dan, ed, fred, gav, hal, ian, jon
And ten females:
abi, bea, cath, dee, eve, fay, gay, hope, ivy, jan
And a complete list of ranked preferences, where the most liked is to the left:
abe: abi, eve, cath, ivy, jan, dee, fay, bea, hope, gay
bob: cath, hope, abi, dee, eve, fay, bea, jan, ivy, gay
col: hope, eve, abi, dee, bea, fay, ivy, gay, cath, jan
dan: ivy, fay, dee, gay, hope, eve, jan, bea, cath, abi
ed: jan, dee, bea, cath, fay, eve, abi, ivy, hope, gay
fred: bea, abi, dee, gay, eve, ivy, cath, jan, hope, fay
gav: gay, eve, ivy, bea, cath, abi, dee, hope, jan, fay
hal: abi, eve, hope, fay, ivy, cath, jan, bea, gay, dee
ian: hope, cath, dee, gay, bea, abi, fay, ivy, jan, eve
jon: abi, fay, jan, gay, eve, bea, dee, cath, ivy, hope
abi: bob, fred, jon, gav, ian, abe, dan, ed, col, hal
bea: bob, abe, col, fred, gav, dan, ian, ed, jon, hal
cath: fred, bob, ed, gav, hal, col, ian, abe, dan, jon
dee: fred, jon, col, abe, ian, hal, gav, dan, bob, ed
eve: jon, hal, fred, dan, abe, gav, col, ed, ian, bob
fay: bob, abe, ed, ian, jon, dan, fred, gav, col, hal
gay: jon, gav, hal, fred, bob, abe, col, ed, dan, ian
hope: gav, jon, bob, abe, ian, dan, hal, ed, col, fred
ivy: ian, col, hal, gav, fred, bob, abe, ed, jon, dan
jan: ed, hal, gav, abe, bob, jon, col, ian, fred, dan
Use the Gale Shapley algorithm to find a stable set of engagements
Perturb this set of engagements to form an unstable set of engagements then check this new set for stability.
References
The Stable Marriage Problem. (Eloquent description and background information).
Gale-Shapley Algorithm Demonstration.
Another Gale-Shapley Algorithm Demonstration.
Stable Marriage Problem - Numberphile (Video).
Stable Marriage Problem (the math bit) (Video).
The Stable Marriage Problem and School Choice. (Excellent exposition)
| #VBA | VBA | 2 methods will be shown here:
1 - using basic VBA-features for strings
2 - using the scripting.dictionary library |
http://rosettacode.org/wiki/Stack | Stack |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also called LIFO.
The stack is accessed through its top.
The basic stack operations are:
push stores a new element onto the stack top;
pop returns the last pushed stack element, while removing it from the stack;
empty tests if the stack contains no elements.
Sometimes the last pushed stack element is made accessible for immutable access (for read) or mutable access (for write):
top (sometimes called peek to keep with the p theme) returns the topmost element without modifying the stack.
Stacks allow a very simple hardware implementation.
They are common in almost all processors.
In programming, stacks are also very popular for their way (LIFO) of resource management, usually memory.
Nested scopes of language objects are naturally implemented by a stack (sometimes by multiple stacks).
This is a classical way to implement local variables of a re-entrant or recursive subprogram. Stacks are also used to describe a formal computational framework.
See stack machine.
Many algorithms in pattern matching, compiler construction (e.g. recursive descent parsers), and machine learning (e.g. based on tree traversal) have a natural representation in terms of stacks.
Task
Create a stack supporting the basic operations: push, pop, empty.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
| #Logtalk | Logtalk |
:- object(stack).
:- public(push/3).
push(Element, Stack, [Element| Stack]).
:- public(pop/3).
pop([Top| Stack], Top, Stack).
:- public(empty/1)
empty([]).
:- end_object.
|
http://rosettacode.org/wiki/Spiral_matrix | Spiral matrix | Task
Produce a spiral array.
A spiral array is a square arrangement of the first N2 natural numbers, where the
numbers increase sequentially as you go around the edges of the array spiraling inwards.
For example, given 5, produce this array:
0 1 2 3 4
15 16 17 18 5
14 23 24 19 6
13 22 21 20 7
12 11 10 9 8
Related tasks
Zig-zag matrix
Identity_matrix
Ulam_spiral_(for_primes)
| #MiniZinc | MiniZinc |
%Spiral Matrix. Nigel Galloway, February 3rd., 2020
int: Size;
array [1..Size,1..Size] of var 1..Size*Size: spiral;
constraint spiral[1,1..]=1..Size;
constraint forall(n in 2..(Size+1) div 2)(forall(g in n..Size+1-n)(spiral[n,g]=spiral[n,g-1]+1));
constraint forall(n in 1..(Size+1) div 2)(forall(g in n+1..Size+1-n)(spiral[g,Size-n+1]=spiral[g-1,Size-n+1]+1));
constraint forall(n in 1..Size div 2)(forall(g in n..Size-n)(spiral[Size-n+1,g]=spiral[Size-n+1,g+1]+1)) /\ forall(n in 1..Size div 2)(forall(g in n+1..Size-n)(spiral[g,n]=spiral[g+1,n]+1));
output [show2d(spiral)];
|
http://rosettacode.org/wiki/Sorting_algorithms/Radix_sort | Sorting algorithms/Radix sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an integer array with the radix sort algorithm.
The primary purpose is to complete the characterization of sort algorithms task.
| #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | ClearAll[SortByPos, RadixSort]
SortByPos[data : {_List ..}, pos_Integer] := Module[{digs, order},
digs = data[[All, pos]];
order = Ordering[digs];
data[[order]]
]
RadixSort[x : {_Integer ..}] := Module[{y, digs, maxlen, offset},
offset = Min[x];
y = x - offset;
digs = IntegerDigits /@ y;
maxlen = Max[Length /@ digs];
digs = IntegerDigits[#, 10, maxlen] & /@ y;
digs = Fold[SortByPos, digs, -Range[maxlen]];
digs = FromDigits /@ digs;
digs += offset;
digs
] |
http://rosettacode.org/wiki/Sorting_algorithms/Radix_sort | Sorting algorithms/Radix sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an integer array with the radix sort algorithm.
The primary purpose is to complete the characterization of sort algorithms task.
| #Nim | Nim | func radixSort[T](a: openArray[T]): seq[T] =
result = @a
## Loop for every bit in the integers.
for shift in countdown(63, 0):
var tmp = newSeq[T](result.len) # The array to put the partially sorted array into.
var j = 0 # The number of 0s.
for i in 0..result.high:
# If there is a 1 in the bit we are testing, the number will be negative.
let move = result[i] shl shift >= 0
# If this is the last bit, negative numbers are actually lower.
let toBeMoved = if shift == 0: not move else: move
if toBeMoved:
tmp[j] = result[i]
inc j
else:
# It's a 1, so stick it in the result array for now.
result[i - j] = result[i]
# Copy over the 1s from the old array.
for i in j..tmp.high:
tmp[i] = result[i - j]
# And now the tmp array gets switched for another round of sorting.
result.shallowCopy(tmp)
when isMainModule:
const arrays = [@[170, 45, 75, -90, -802, 24, 2, 66],
@[-4, 5, -26, 58, -990, 331, 331, 990, -1837, 2028]]
for a in arrays:
echo radixSort(a) |
http://rosettacode.org/wiki/Sorting_algorithms/Quicksort | Sorting algorithms/Quicksort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
This page uses content from Wikipedia. The original article was at Quicksort. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Sort an array (or list) elements using the quicksort algorithm.
The elements must have a strict weak order and the index of the array can be of any discrete type.
For languages where this is not possible, sort an array of integers.
Quicksort, also known as partition-exchange sort, uses these steps.
Choose any element of the array to be the pivot.
Divide all other elements (except the pivot) into two partitions.
All elements less than the pivot must be in the first partition.
All elements greater than the pivot must be in the second partition.
Use recursion to sort both partitions.
Join the first sorted partition, the pivot, and the second sorted partition.
The best pivot creates partitions of equal length (or lengths differing by 1).
The worst pivot creates an empty partition (for example, if the pivot is the first or last element of a sorted array).
The run-time of Quicksort ranges from O(n log n) with the best pivots, to O(n2) with the worst pivots, where n is the number of elements in the array.
This is a simple quicksort algorithm, adapted from Wikipedia.
function quicksort(array)
less, equal, greater := three empty arrays
if length(array) > 1
pivot := select any element of array
for each x in array
if x < pivot then add x to less
if x = pivot then add x to equal
if x > pivot then add x to greater
quicksort(less)
quicksort(greater)
array := concatenate(less, equal, greater)
A better quicksort algorithm works in place, by swapping elements within the array, to avoid the memory allocation of more arrays.
function quicksort(array)
if length(array) > 1
pivot := select any element of array
left := first index of array
right := last index of array
while left ≤ right
while array[left] < pivot
left := left + 1
while array[right] > pivot
right := right - 1
if left ≤ right
swap array[left] with array[right]
left := left + 1
right := right - 1
quicksort(array from first index to right)
quicksort(array from left to last index)
Quicksort has a reputation as the fastest sort. Optimized variants of quicksort are common features of many languages and libraries. One often contrasts quicksort with merge sort, because both sorts have an average time of O(n log n).
"On average, mergesort does fewer comparisons than quicksort, so it may be better when complicated comparison routines are used. Mergesort also takes advantage of pre-existing order, so it would be favored for using sort() to merge several sorted arrays. On the other hand, quicksort is often faster for small arrays, and on arrays of a few distinct values, repeated many times." — http://perldoc.perl.org/sort.html
Quicksort is at one end of the spectrum of divide-and-conquer algorithms, with merge sort at the opposite end.
Quicksort is a conquer-then-divide algorithm, which does most of the work during the partitioning and the recursive calls. The subsequent reassembly of the sorted partitions involves trivial effort.
Merge sort is a divide-then-conquer algorithm. The partioning happens in a trivial way, by splitting the input array in half. Most of the work happens during the recursive calls and the merge phase.
With quicksort, every element in the first partition is less than or equal to every element in the second partition. Therefore, the merge phase of quicksort is so trivial that it needs no mention!
This task has not specified whether to allocate new arrays, or sort in place. This task also has not specified how to choose the pivot element. (Common ways to are to choose the first element, the middle element, or the median of three elements.) Thus there is a variety among the following implementations.
| #ATS | ATS | (*------------------------------------------------------------------*)
(* Quicksort in ATS2, for non-linear lists. *)
(*------------------------------------------------------------------*)
#include "share/atspre_staload.hats"
#define NIL list_nil ()
#define :: list_cons
(*------------------------------------------------------------------*)
(* A simple quicksort working on "garbage-collected" linked lists,
with first element as pivot. This is meant as a demonstration, not
as a superior sort algorithm.
It is based on the "not-in-place" task pseudocode. *)
datatype comparison_result =
| first_is_less_than_second of ()
| first_is_equal_to_second of ()
| first_is_greater_than_second of ()
extern fun {a : t@ype}
list_quicksort$comparison (x : a, y : a) :<> comparison_result
extern fun {a : t@ype}
list_quicksort {n : int}
(lst : list (a, n)) :<> list (a, n)
(* - - - - - - - - - - - - - - - - - - - - - - *)
implement {a}
list_quicksort {n} (lst) =
let
fun
partition {n : nat}
.<n>. (* Proof of termination. *)
(lst : list (a, n),
pivot : a)
:<> [n1, n2, n3 : int | n1 + n2 + n3 == n]
@(list (a, n1), list (a, n2), list (a, n3)) =
(* This implementation is *not* tail recursive. I may get a
scolding for using ATS to risk stack overflow! However, I
need more practice writing non-tail routines. :) Also, a lot
of programmers in other languages would do it this
way--especially if the lists are evaluated lazily. *)
case+ lst of
| NIL => @(NIL, NIL, NIL)
| head :: tail =>
let
val @(lt, eq, gt) = partition (tail, pivot)
prval () = lemma_list_param lt
prval () = lemma_list_param eq
prval () = lemma_list_param gt
in
case+ list_quicksort$comparison<a> (head, pivot) of
| first_is_less_than_second () => @(head :: lt, eq, gt)
| first_is_equal_to_second () => @(lt, head :: eq, gt)
| first_is_greater_than_second () => @(lt, eq, head :: gt)
end
fun
quicksort {n : nat}
.<n>. (* Proof of termination. *)
(lst : list (a, n))
:<> list (a, n) =
case+ lst of
| NIL => lst
| _ :: NIL => lst
| head :: tail =>
let
(* We are careful here to run "partition" on "tail" rather
than "lst", so the termination metric will be provably
decreasing. (Really the compiler *forces* us to take such
care, or else to change :<> to :<!ntm>) *)
val pivot = head
prval () = lemma_list_param tail
val @(lt, eq, gt) = partition {n - 1} (tail, pivot)
prval () = lemma_list_param lt
prval () = lemma_list_param eq
prval () = lemma_list_param gt
val eq = pivot :: eq
and lt = quicksort lt
and gt = quicksort gt
in
lt + (eq + gt)
end
prval () = lemma_list_param lst
in
quicksort {n} lst
end
(*------------------------------------------------------------------*)
val example_strings =
$list ("choose", "any", "element", "of", "the", "array",
"to", "be", "the", "pivot",
"divide", "all", "other", "elements", "except",
"the", "pivot", "into", "two", "partitions",
"all", "elements", "less", "than", "the", "pivot",
"must", "be", "in", "the", "first", "partition",
"all", "elements", "greater", "than", "the", "pivot",
"must", "be", "in", "the", "second", "partition",
"use", "recursion", "to", "sort", "both", "partitions",
"join", "the", "first", "sorted", "partition", "the",
"pivot", "and", "the", "second", "sorted", "partition")
implement
list_quicksort$comparison<string> (x, y) =
let
val i = strcmp (x, y)
in
if i < 0 then
first_is_less_than_second
else if i = 0 then
first_is_equal_to_second
else
first_is_greater_than_second
end
implement
main0 () =
let
val sorted_strings = list_quicksort<string> example_strings
fun
print_strings {n : nat} .<n>.
(strings : list (string, n),
i : int) : void =
case+ strings of
| NIL => if i <> 1 then println! () else ()
| head :: tail =>
begin
print! head;
if i = 8 then
begin
println! ();
print_strings (tail, 1)
end
else
begin
print! " ";
print_strings (tail, succ i)
end
end
in
println! (length example_strings);
println! (length sorted_strings);
print_strings (sorted_strings, 1)
end
(*------------------------------------------------------------------*) |
http://rosettacode.org/wiki/Sorting_algorithms/Patience_sort | Sorting algorithms/Patience sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Sort an array of numbers (of any convenient size) into ascending order using Patience sorting.
Related task
Longest increasing subsequence
| #Java | Java | import java.util.*;
public class PatienceSort {
public static <E extends Comparable<? super E>> void sort (E[] n) {
List<Pile<E>> piles = new ArrayList<Pile<E>>();
// sort into piles
for (E x : n) {
Pile<E> newPile = new Pile<E>();
newPile.push(x);
int i = Collections.binarySearch(piles, newPile);
if (i < 0) i = ~i;
if (i != piles.size())
piles.get(i).push(x);
else
piles.add(newPile);
}
// priority queue allows us to retrieve least pile efficiently
PriorityQueue<Pile<E>> heap = new PriorityQueue<Pile<E>>(piles);
for (int c = 0; c < n.length; c++) {
Pile<E> smallPile = heap.poll();
n[c] = smallPile.pop();
if (!smallPile.isEmpty())
heap.offer(smallPile);
}
assert(heap.isEmpty());
}
private static class Pile<E extends Comparable<? super E>> extends Stack<E> implements Comparable<Pile<E>> {
public int compareTo(Pile<E> y) { return peek().compareTo(y.peek()); }
}
public static void main(String[] args) {
Integer[] a = {4, 65, 2, -31, 0, 99, 83, 782, 1};
sort(a);
System.out.println(Arrays.toString(a));
}
} |
http://rosettacode.org/wiki/Sorting_algorithms/Insertion_sort | Sorting algorithms/Insertion sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
This page uses content from Wikipedia. The original article was at Insertion sort. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
An O(n2) sorting algorithm which moves elements one at a time into the correct position.
The algorithm consists of inserting one element at a time into the previously sorted part of the array, moving higher ranked elements up as necessary.
To start off, the first (or smallest, or any arbitrary) element of the unsorted array is considered to be the sorted part.
Although insertion sort is an O(n2) algorithm, its simplicity, low overhead, good locality of reference and efficiency make it a good choice in two cases:
small n,
as the final finishing-off algorithm for O(n logn) algorithms such as mergesort and quicksort.
The algorithm is as follows (from wikipedia):
function insertionSort(array A)
for i from 1 to length[A]-1 do
value := A[i]
j := i-1
while j >= 0 and A[j] > value do
A[j+1] := A[j]
j := j-1
done
A[j+1] = value
done
Writing the algorithm for integers will suffice.
| #ALGOL_W | ALGOL W | % insertion sorts in-place the array A. As Algol W procedures can't find the bounds %
% of an array parameter, the lower and upper bounds must be specified in lb and ub %
procedure insertionSortI ( integer array A ( * ); integer value lb, ub ) ;
for i := lb + 1 until ub do begin
integer v, j;
v := A( i );
j := i - 1;
while j >= lb and A( j ) > v do begin
A( j + 1 ) := A( j );
j := j - 1
end while_j_ge_0_and_Aj_gt_v ;
A( j + 1 ) := v
end insertionSortI ; |
http://rosettacode.org/wiki/Sorting_algorithms/Permutation_sort | Sorting algorithms/Permutation sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Implement a permutation sort, which proceeds by generating the possible permutations
of the input array/list until discovering the sorted one.
Pseudocode:
while not InOrder(list) do
nextPermutation(list)
done
| #PARI.2FGP | PARI/GP | permutationSort(v)={
my(u);
for(k=1,(#v)!,
u=vecextract(v, numtoperm(#v,k));
for(i=2,#u,
if(u[i]<u[i-1], next(2))
);
return(u)
)
}; |
http://rosettacode.org/wiki/Sorting_algorithms/Permutation_sort | Sorting algorithms/Permutation sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Implement a permutation sort, which proceeds by generating the possible permutations
of the input array/list until discovering the sorted one.
Pseudocode:
while not InOrder(list) do
nextPermutation(list)
done
| #Perl | Perl | sub psort {
my ($x, $d) = @_;
unless ($d //= $#$x) {
$x->[$_] < $x->[$_ - 1] and return for 1 .. $#$x;
return 1
}
for (0 .. $d) {
unshift @$x, splice @$x, $d, 1;
next if $x->[$d] < $x->[$d - 1];
return 1 if psort($x, $d - 1);
}
}
my @a = map+(int rand 100), 0 .. 10;
print "Before:\t@a\n";
psort(\@a);
print "After:\t@a\n" |
http://rosettacode.org/wiki/Sorting_algorithms/Pancake_sort | Sorting algorithms/Pancake sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array of integers (of any convenient size) into ascending order using Pancake sorting.
In short, instead of individual elements being sorted, the only operation allowed is to "flip" one end of the list, like so:
Before: 6 7 8 9 2 5 3 4 1
After: 9 8 7 6 2 5 3 4 1
Only one end of the list can be flipped; this should be the low end, but the high end is okay if it's easier to code or works better, but it must be the same end for the entire solution. (The end flipped can't be arbitrarily changed.)
Show both the initial, unsorted list and the final sorted list.
(Intermediate steps during sorting are optional.)
Optimizations are optional (but recommended).
Related tasks
Number reversal game
Topswops
Also see
Wikipedia article: pancake sorting.
| #Fortran | Fortran | program Pancake_Demo
implicit none
integer :: list(8) = (/ 1, 4, 7, 2, 5, 8, 3, 6 /)
call Pancake_sort(list)
contains
subroutine Pancake_sort(a)
integer, intent(in out) :: a(:)
integer :: i, maxpos
write(*,*) a
do i = size(a), 2, -1
! Find position of max number between index 1 and i
maxpos = maxloc(a(1:i), 1)
! is it in the correct position already?
if (maxpos == i) cycle
! is it at the beginning of the array? If not flip array section so it is
if (maxpos /= 1) then
a(1:maxpos) = a(maxpos:1:-1)
write(*,*) a
end if
! Flip array section to get max number to correct position
a(1:i) = a(i:1:-1)
write(*,*) a
end do
end subroutine
end program Pancake_Demo |
http://rosettacode.org/wiki/Sorting_algorithms/Stooge_sort | Sorting algorithms/Stooge sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
This page uses content from Wikipedia. The original article was at Stooge sort. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Show the Stooge Sort for an array of integers.
The Stooge Sort algorithm is as follows:
algorithm stoogesort(array L, i = 0, j = length(L)-1)
if L[j] < L[i] then
L[i] ↔ L[j]
if j - i > 1 then
t := (j - i + 1)/3
stoogesort(L, i , j-t)
stoogesort(L, i+t, j )
stoogesort(L, i , j-t)
return L
| #OCaml | OCaml | let swap ar i j =
let tmp = ar.(i) in
ar.(i) <- ar.(j);
ar.(j) <- tmp
let stoogesort ar =
let rec aux i j =
if ar.(j) < ar.(i) then
swap ar i j
else if j - i > 1 then begin
let t = (j - i + 1) / 3 in
aux (i) (j-t);
aux (i+t) (j);
aux (i) (j-t);
end
in
aux 0 (Array.length ar - 1) |
http://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort | Sorting algorithms/Sleep sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
In general, sleep sort works by starting a separate task for each item to be sorted, where each task sleeps for an interval corresponding to the item's sort key, then emits the item. Items are then collected sequentially in time.
Task: Write a program that implements sleep sort. Have it accept non-negative integers on the command line and print the integers in sorted order. If this is not idomatic in your language or environment, input and output may be done differently. Enhancements for optimization, generalization, practicality, robustness, and so on are not required.
Sleep sort was presented anonymously on 4chan and has been discussed on Hacker News.
| #Sidef | Sidef | ARGV.map{.to_i}.map{ |i|
{Sys.sleep(i); say i}.fork;
}.each{.wait}; |
http://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort | Sorting algorithms/Sleep sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
In general, sleep sort works by starting a separate task for each item to be sorted, where each task sleeps for an interval corresponding to the item's sort key, then emits the item. Items are then collected sequentially in time.
Task: Write a program that implements sleep sort. Have it accept non-negative integers on the command line and print the integers in sorted order. If this is not idomatic in your language or environment, input and output may be done differently. Enhancements for optimization, generalization, practicality, robustness, and so on are not required.
Sleep sort was presented anonymously on 4chan and has been discussed on Hacker News.
| #Simula | Simula | SIMULATION
BEGIN
PROCESS CLASS SORTITEM(N); INTEGER N;
BEGIN
HOLD(N);
OUTINT(N, 3);
END;
INTEGER I;
FOR I := 3, 2, 4, 7, 3, 6, 9, 1 DO
BEGIN
REF(SORTITEM) SI;
SI :- NEW SORTITEM(I);
ACTIVATE SI;
END;
HOLD(100000);
OUTIMAGE;
END; |
http://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort | Sorting algorithms/Sleep sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
In general, sleep sort works by starting a separate task for each item to be sorted, where each task sleeps for an interval corresponding to the item's sort key, then emits the item. Items are then collected sequentially in time.
Task: Write a program that implements sleep sort. Have it accept non-negative integers on the command line and print the integers in sorted order. If this is not idomatic in your language or environment, input and output may be done differently. Enhancements for optimization, generalization, practicality, robustness, and so on are not required.
Sleep sort was presented anonymously on 4chan and has been discussed on Hacker News.
| #SNUSP | SNUSP |
/$>\ input until eof
#/?<\?,/ foreach: fork
\ &/:+ copy and\
/:\?-; delay /
\.# print and exit thread
|
http://rosettacode.org/wiki/Sorting_algorithms/Selection_sort | Sorting algorithms/Selection sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array (or list) of elements using the Selection sort algorithm.
It works as follows:
First find the smallest element in the array and exchange it with the element in the first position, then find the second smallest element and exchange it with the element in the second position, and continue in this way until the entire array is sorted.
Its asymptotic complexity is O(n2) making it inefficient on large arrays.
Its primary purpose is for when writing data is very expensive (slow) when compared to reading, eg. writing to flash memory or EEPROM.
No other sorting algorithm has less data movement.
References
Rosetta Code: O (complexity).
Wikipedia: Selection sort.
Wikipedia: [Big O notation].
| #Erlang | Erlang |
-module(solution).
-import(lists,[delete/2,max/1]).
-compile(export_all).
selection_sort([],Sort)-> Sort;
selection_sort(Ar,Sort)->
M=max(Ar),
Ad=delete(M,Ar),
selection_sort(Ad,[M|Sort]).
print_array([])->ok;
print_array([H|T])->
io:format("~p~n",[H]),
print_array(T).
main()->
Ans=selection_sort([1,5,7,8,4,10],[]),
print_array(Ans).
|
http://rosettacode.org/wiki/Soundex | Soundex | Soundex is an algorithm for creating indices for words based on their pronunciation.
Task
The goal is for homophones to be encoded to the same representation so that they can be matched despite minor differences in spelling (from the soundex Wikipedia article).
Caution
There is a major issue in many of the implementations concerning the separation of two consonants that have the same soundex code! According to the official Rules [[1]]. So check for instance if Ashcraft is coded to A-261.
If a vowel (A, E, I, O, U) separates two consonants that have the same soundex code, the consonant to the right of the vowel is coded. Tymczak is coded as T-522 (T, 5 for the M, 2 for the C, Z ignored (see "Side-by-Side" rule above), 2 for the K). Since the vowel "A" separates the Z and K, the K is coded.
If "H" or "W" separate two consonants that have the same soundex code, the consonant to the right of the vowel is not coded. Example: Ashcraft is coded A-261 (A, 2 for the S, C ignored, 6 for the R, 1 for the F). It is not coded A-226.
| #FreeBASIC | FreeBASIC |
Function getCode(c As String) As String
If Instr("BFPV", c) Then Return "1"
If Instr("CGJKQSXZ", c) Then Return "2"
If Instr("DT", c) Then Return "3"
If "L" = c Then Return "4"
If Instr("MN", c) Then Return "5"
If "R" = c Then Return "6"
If Instr("HW", c) Then Return "."
End Function
Function Soundex(palabra As String) As String
palabra = Ucase(palabra)
Dim As String code = Mid(palabra,1,1)
Dim As String previo = getCode(Left(palabra, 1)) ''""
Dim As String actual
For i As Byte = 2 To (Len(palabra) + 1)
actual = getCode(Mid(palabra, i, 1))
If actual = "." Then Continue For
If Len(actual) > 0 And actual <> previo Then code &= actual
previo = actual
If Len(code) = 4 Then Exit For
Next i
If Len(code) < 4 Then code &= String(4,"0")
Return Left(code,4)
End Function
Dim As String nombre
For i As Byte = 1 To 20
Read nombre
Print """"; nombre; """"; Tab(15); Soundex(nombre)
Next i
Data "Aschraft", "Ashcroft", "Euler", "Gauss", "Ghosh", "Hilbert", "Heilbronn", "Lee", "Lissajous", "Lloyd"
Data "Moses", "Pfister", "Robert", "Rupert", "Rubin", "Tymczak", "VanDeusen", "Wheaton", "Soundex", "Example"
Sleep
|
http://rosettacode.org/wiki/Sorting_algorithms/Shell_sort | Sorting algorithms/Shell sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array of elements using the Shell sort algorithm, a diminishing increment sort.
The Shell sort (also known as Shellsort or Shell's method) is named after its inventor, Donald Shell, who published the algorithm in 1959.
Shell sort is a sequence of interleaved insertion sorts based on an increment sequence.
The increment size is reduced after each pass until the increment size is 1.
With an increment size of 1, the sort is a basic insertion sort, but by this time the data is guaranteed to be almost sorted, which is insertion sort's "best case".
Any sequence will sort the data as long as it ends in 1, but some work better than others.
Empirical studies have shown a geometric increment sequence with a ratio of about 2.2 work well in practice.
[1]
Other good sequences are found at the On-Line Encyclopedia of Integer Sequences.
| #Liberty_BASIC | Liberty BASIC |
siz = 100
dim a(siz)
for i = 1 to siz
a(i) = int(rnd(1) * 1000)
next
' -------------------------------
' Shell Sort
' -------------------------------
incr = int(siz / 2)
WHILE incr > 0
for i = 1 to siz
j = i
temp = a(i)
WHILE (j >= incr+1 and a(abs(j-incr)) > temp)
a(j) = a(j-incr)
j = j - incr
wend
a(j) = temp
next
IF incr = 2 THEN
incr = 1
ELSE
incr = int(incr * (5 / 11))
end if
WEND
for i = 1 to siz
print a(i)
next
|
http://rosettacode.org/wiki/Stable_marriage_problem | Stable marriage problem | Solve the Stable marriage problem using the Gale/Shapley algorithm.
Problem description
Given an equal number of men and women to be paired for marriage, each man ranks all the women in order of his preference and each woman ranks all the men in order of her preference.
A stable set of engagements for marriage is one where no man prefers a woman over the one he is engaged to, where that other woman also prefers that man over the one she is engaged to. I.e. with consulting marriages, there would be no reason for the engagements between the people to change.
Gale and Shapley proved that there is a stable set of engagements for any set of preferences and the first link above gives their algorithm for finding a set of stable engagements.
Task Specifics
Given ten males:
abe, bob, col, dan, ed, fred, gav, hal, ian, jon
And ten females:
abi, bea, cath, dee, eve, fay, gay, hope, ivy, jan
And a complete list of ranked preferences, where the most liked is to the left:
abe: abi, eve, cath, ivy, jan, dee, fay, bea, hope, gay
bob: cath, hope, abi, dee, eve, fay, bea, jan, ivy, gay
col: hope, eve, abi, dee, bea, fay, ivy, gay, cath, jan
dan: ivy, fay, dee, gay, hope, eve, jan, bea, cath, abi
ed: jan, dee, bea, cath, fay, eve, abi, ivy, hope, gay
fred: bea, abi, dee, gay, eve, ivy, cath, jan, hope, fay
gav: gay, eve, ivy, bea, cath, abi, dee, hope, jan, fay
hal: abi, eve, hope, fay, ivy, cath, jan, bea, gay, dee
ian: hope, cath, dee, gay, bea, abi, fay, ivy, jan, eve
jon: abi, fay, jan, gay, eve, bea, dee, cath, ivy, hope
abi: bob, fred, jon, gav, ian, abe, dan, ed, col, hal
bea: bob, abe, col, fred, gav, dan, ian, ed, jon, hal
cath: fred, bob, ed, gav, hal, col, ian, abe, dan, jon
dee: fred, jon, col, abe, ian, hal, gav, dan, bob, ed
eve: jon, hal, fred, dan, abe, gav, col, ed, ian, bob
fay: bob, abe, ed, ian, jon, dan, fred, gav, col, hal
gay: jon, gav, hal, fred, bob, abe, col, ed, dan, ian
hope: gav, jon, bob, abe, ian, dan, hal, ed, col, fred
ivy: ian, col, hal, gav, fred, bob, abe, ed, jon, dan
jan: ed, hal, gav, abe, bob, jon, col, ian, fred, dan
Use the Gale Shapley algorithm to find a stable set of engagements
Perturb this set of engagements to form an unstable set of engagements then check this new set for stability.
References
The Stable Marriage Problem. (Eloquent description and background information).
Gale-Shapley Algorithm Demonstration.
Another Gale-Shapley Algorithm Demonstration.
Stable Marriage Problem - Numberphile (Video).
Stable Marriage Problem (the math bit) (Video).
The Stable Marriage Problem and School Choice. (Excellent exposition)
| #Wren | Wren | import "/dynamic" for Struct
var mPref = {
"abe": [
"abi", "eve", "cath", "ivy", "jan",
"dee", "fay", "bea", "hope", "gay"],
"bob": [
"cath", "hope", "abi", "dee", "eve",
"fay", "bea", "jan", "ivy", "gay"],
"col": [
"hope", "eve", "abi", "dee", "bea",
"fay", "ivy", "gay", "cath", "jan"],
"dan": [
"ivy", "fay", "dee", "gay", "hope",
"eve", "jan", "bea", "cath", "abi"],
"ed": [
"jan", "dee", "bea", "cath", "fay",
"eve", "abi", "ivy", "hope", "gay"],
"fred": [
"bea", "abi", "dee", "gay", "eve",
"ivy", "cath", "jan", "hope", "fay"],
"gav": [
"gay", "eve", "ivy", "bea", "cath",
"abi", "dee", "hope", "jan", "fay"],
"hal": [
"abi", "eve", "hope", "fay", "ivy",
"cath", "jan", "bea", "gay", "dee"],
"ian": [
"hope", "cath", "dee", "gay", "bea",
"abi", "fay", "ivy", "jan", "eve"],
"jon": [
"abi", "fay", "jan", "gay", "eve",
"bea", "dee", "cath", "ivy", "hope"]
}
var wPref = {
"abi": {
"bob": 1, "fred": 2, "jon": 3, "gav": 4, "ian": 5,
"abe": 6, "dan": 7, "ed": 8, "col": 9, "hal": 10},
"bea": {
"bob": 1, "abe": 2, "col": 3, "fred": 4, "gav": 5,
"dan": 6, "ian": 7, "ed": 8, "jon": 9, "hal": 10},
"cath": {
"fred": 1, "bob": 2, "ed": 3, "gav": 4, "hal": 5,
"col": 6, "ian": 7, "abe": 8, "dan": 9, "jon": 10},
"dee": {
"fred": 1, "jon": 2, "col": 3, "abe": 4, "ian": 5,
"hal": 6, "gav": 7, "dan": 8, "bob": 9, "ed": 10},
"eve": {
"jon": 1, "hal": 2, "fred": 3, "dan": 4, "abe": 5,
"gav": 6, "col": 7, "ed": 8, "ian": 9, "bob": 10},
"fay": {
"bob": 1, "abe": 2, "ed": 3, "ian": 4, "jon": 5,
"dan": 6, "fred": 7, "gav": 8, "col": 9, "hal": 10},
"gay": {
"jon": 1, "gav": 2, "hal": 3, "fred": 4, "bob": 5,
"abe": 6, "col": 7, "ed": 8, "dan": 9, "ian": 10},
"hope": {
"gav": 1, "jon": 2, "bob": 3, "abe": 4, "ian": 5,
"dan": 6, "hal": 7, "ed": 8, "col": 9, "fred": 10},
"ivy": {
"ian": 1, "col": 2, "hal": 3, "gav": 4, "fred": 5,
"bob": 6, "abe": 7, "ed": 8, "jon": 9, "dan": 10},
"jan": {
"ed": 1, "hal": 2, "gav": 3, "abe": 4, "bob": 5,
"jon": 6, "col": 7, "ian": 8, "fred": 9, "dan": 10}
}
// Pair implements the Gale/Shapely algorithm.
var pair = Fn.new { |pPref, rPref|
// code is destructive on the maps, so work with copies
var pFree = {}
for (me in pPref) pFree[me.key] = me.value
var rFree = {}
for (me in rPref) rFree[me.key] = me.value
// struct only used in this function.
// preferences must be saved in case engagement is broken.
var Save = Struct.create("Save", ["proposer", "pPref", "rPref"])
var proposals = {} // key is recipient (w)
// WP pseudocode comments prefaced with WP: m is proposer, w is recipient.
// WP: while ∃ free man m who still has a woman w to propose to
while (pFree.count > 0) { // while there is a free proposer,
var proposer
var ppref
for (me in pFree) {
proposer = me.key
ppref = me.value
break // pick a proposer at random, whatever map iteration delivers first.
}
if (ppref.count == 0) continue // if proposer has no possible recipients, skip
// WP: w = m's highest ranked such woman to whom he has not yet proposed
var recipient = ppref[0] // highest ranged is first in list.
ppref = ppref[1..-1] // pop from list
var rpref = {}
// WP: if w is free
if (rpref = rFree[recipient]) {
// WP: (m, w) become engaged
// (common code follows if statement)
} else {
// WP: else some pair (m', w) already exists
var s = proposals[recipient] // get proposal saved preferences
// WP: if w prefers m to m'
if (s.rPref[proposer] < s.rPref[s.proposer]) {
System.print("engagement broken: %(recipient) %(s.proposer)")
// WP: m' becomes free
pFree[s.proposer] = s.pPref // return proposer to the map
// WP: (m, w) become engaged
rpref = s.rPref
// (common code follows if statement)
} else {
// WP: else (m', w) remain engaged
pFree[proposer] = ppref // update preferences in map
continue
}
}
System.print("engagement: %(recipient) %(proposer)")
proposals[recipient] = Save.new(proposer, ppref, rpref)
pFree.remove(proposer)
rFree.remove(recipient)
}
// construct return value
var ps = {}
for (me in proposals) {
ps[me.key] = me.value.proposer
}
return ps
}
var validateStable = Fn.new { |ps, pPref, rPref|
for (me in ps) System.print("%(me.key) %(me.value)")
for (me in ps) {
var r = me.key
var p = me.value
for (rp in pPref[p]) {
if (rp == r) break
var rprefs = rPref[rp]
if (rprefs[p] < rprefs[ps[rp]]) {
System.print("unstable.")
System.print("%(p) and %(rp) would prefer each other over their current pairings.")
return false
}
}
}
System.print("stable.")
return true
}
// get parings by Gale/Shapley algorithm
var ps = pair.call(mPref, wPref)
// show results
System.print("\nresult:")
if (!validateStable.call(ps, mPref, wPref)) return
// perturb
while (true) {
var i = 0
var w2 = List.filled(2, null)
var m2 = List.filled(2, null)
for (me in ps) {
w2[i] = me.key
m2[i] = me.value
if (i == 1) break
i = i + 1
}
System.print("\nexchanging partners of %(m2[0]) and %(m2[1])")
ps[w2[0]] = m2[1]
ps[w2[1]] = m2[0]
// validate perturbed parings
if (!validateStable.call(ps, mPref, wPref)) return
// if those happened to be stable as well, perturb more
} |
http://rosettacode.org/wiki/Stack | Stack |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also called LIFO.
The stack is accessed through its top.
The basic stack operations are:
push stores a new element onto the stack top;
pop returns the last pushed stack element, while removing it from the stack;
empty tests if the stack contains no elements.
Sometimes the last pushed stack element is made accessible for immutable access (for read) or mutable access (for write):
top (sometimes called peek to keep with the p theme) returns the topmost element without modifying the stack.
Stacks allow a very simple hardware implementation.
They are common in almost all processors.
In programming, stacks are also very popular for their way (LIFO) of resource management, usually memory.
Nested scopes of language objects are naturally implemented by a stack (sometimes by multiple stacks).
This is a classical way to implement local variables of a re-entrant or recursive subprogram. Stacks are also used to describe a formal computational framework.
See stack machine.
Many algorithms in pattern matching, compiler construction (e.g. recursive descent parsers), and machine learning (e.g. based on tree traversal) have a natural representation in terms of stacks.
Task
Create a stack supporting the basic operations: push, pop, empty.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
| #LOLCODE | LOLCODE | HAI 2.3
HOW IZ I Init YR Stak
Stak HAS A Length ITZ 0
IF U SAY SO
HOW IZ I Push YR Stak AN YR Value
Stak HAS A SRS Stak'Z Length ITZ Value
Stak'Z Length R SUM OF Stak'Z Length AN 1
IF U SAY SO
HOW IZ I Top YR Stak
FOUND YR Stak'Z SRS DIFF OF Stak'Z Length AN 1
IF U SAY SO
HOW IZ I Pop YR Stak
I HAS A Top ITZ I IZ Top YR Stak MKAY
Stak'Z Length R DIFF OF Stak'Z Length AN 1
FOUND YR Top
IF U SAY SO
HOW IZ I Empty YR Stak
FOUND YR BOTH SAEM 0 AN Stak'Z Length
IF U SAY SO
I HAS A Stak ITZ A BUKKIT
I IZ Init YR Stak MKAY
I IZ Push YR Stak AN YR "Fred" MKAY
I IZ Push YR Stak AN YR "Wilma" MKAY
I IZ Push YR Stak AN YR "Betty" MKAY
I IZ Push YR Stak AN YR "Barney" MKAY
IM IN YR LOOP UPPIN YR Dummy TIL I IZ Empty YR Stak MKAY
VISIBLE I IZ Pop YR Stak MKAY
IM OUTTA YR LOOP
KTHXBYE |
http://rosettacode.org/wiki/Spiral_matrix | Spiral matrix | Task
Produce a spiral array.
A spiral array is a square arrangement of the first N2 natural numbers, where the
numbers increase sequentially as you go around the edges of the array spiraling inwards.
For example, given 5, produce this array:
0 1 2 3 4
15 16 17 18 5
14 23 24 19 6
13 22 21 20 7
12 11 10 9 8
Related tasks
Zig-zag matrix
Identity_matrix
Ulam_spiral_(for_primes)
| #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref symbols binary
parse arg size .
if \size.datatype('W') then do
printArray(generateArray(3))
say
printArray(generateArray(4))
say
printArray(generateArray(5))
say
end
else do
printArray(generateArray(size))
say
end
return
-- -----------------------------------------------------------------------------
method generateArray(dimension = int) private static returns int[,]
-- the output array
array = int[dimension, dimension]
-- get the number of squares, including the center one if
-- the dimension is odd
squares = dimension % 2 + dimension // 2
-- length of a side for the current square
sidelength = dimension
current = 0
loop i_ = 0 to squares - 1
-- do each side of the current square
-- top side
loop j_ = 0 to sidelength - 1
array[i_, i_ + j_] = current
current = current + 1
end j_
-- down the right side
loop j_ = 1 to sidelength - 1
array[i_ + j_, dimension - 1 - i_] = current
current = current + 1
end j_
-- across the bottom
loop j_ = sidelength - 2 to 0 by -1
array[dimension - 1 - i_, i_ + j_] = current
current = current + 1
end j_
-- and up the left side
loop j_ = sidelength - 2 to 1 by -1
array[i_ + j_, i_] = current
current = current + 1
end j_
-- reduce the length of the side by two rows
sidelength = sidelength - 2
end i_
return array
-- -----------------------------------------------------------------------------
method printArray(array = int[,]) private static
dimension = array[1].length
rl = formatSize(array)
loop i_ = 0 to dimension - 1
line = Rexx("|")
loop j_ = 0 to dimension - 1
line = line Rexx(array[i_, j_]).right(rl)
end j_
line = line "|"
say line
end i_
return
-- -----------------------------------------------------------------------------
method formatSize(array = int[,]) private static returns Rexx
dim = array[1].length
maxNum = Rexx(dim * dim - 1).length()
return maxNum
|
http://rosettacode.org/wiki/Sorting_algorithms/Radix_sort | Sorting algorithms/Radix sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an integer array with the radix sort algorithm.
The primary purpose is to complete the characterization of sort algorithms task.
| #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref symbols nobinary
runSample(arg)
return
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method radixSort(tlist = Rexx[]) public static returns Rexx[]
-- scale the array to start at zero to allow handling of -ve values
parse getLimits(tlist) maxn minn maxl .
tlist = rescale(tlist, minn)
loop px = maxl to 1 by -1
bukits = ''
loop ix = 0 to tlist.length - 1
cval = tlist[ix].right(maxl, 0)
parse cval . =(px) digit +1 .
bukits[digit] = bukits[digit] (cval + 0) -- simulates a stack
end ix
intermediates = ''
loop bi = 0 to 9
intermediates = intermediates bukits[bi] -- sumulates unstack
end bi
-- reload array
loop iw = 1 to intermediates.words()
tlist[iw - 1] = intermediates.word(iw)
end iw
end px
-- restore the array to original scale
tlist = rescale(tlist, -minn)
return tlist
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method rescale(arry = Rexx[], newbase) private static returns Rexx[]
loop ix = 0 to arry.length - 1
arry[ix] = arry[ix] - newbase
end ix
return arry
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method getLimits(arry = Rexx[]) private static returns Rexx
maxn = 0
minn = 0
maxl = 0
loop i_ = 0 to arry.length - 1
maxn = maxn.max(arry[i_])
minn = minn.min(arry[i_])
end i_
maxl = (maxn - minn).length()
return maxn minn maxl
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method runSample(arg) private static
lists = [-
[2, 24, 45, 0, 66, 75, 170, -802, -90, 1066, 666], -
[170, 45, 75, 90, 2, 24, 802, 66], -
[10, 9, 8, 7, 8, 5, 4, 3, 2, 1, 0], -
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10], -
[-10, -9, -8, -7, -8, -5, -4, -3, -2, -1, -0], -
[-0, -1, -2, -3, -4, -5, -6, -7, -8, -9, -10], -
[-10, -19, -18, -17, -18, -15, -14, -13, -12, -11, -100], -
[10, 9, 8, 7, 8, 5, 4, 3, 2, 1, 0, -0, -1, -2, -3, -4, -5, -6, -7, -8, -9, -10], -
[-10, -9, -8, -7, -8, -5, -4, -3, -2, -1, -0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] -
]
loop il = 0 to lists.length - 1
tlist = lists[il]
say ' Input:' Arrays.asList(tlist)
say 'Output:' Arrays.asList(radixSort(tlist))
say
end il
return
|
http://rosettacode.org/wiki/Sorting_algorithms/Quicksort | Sorting algorithms/Quicksort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
This page uses content from Wikipedia. The original article was at Quicksort. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Sort an array (or list) elements using the quicksort algorithm.
The elements must have a strict weak order and the index of the array can be of any discrete type.
For languages where this is not possible, sort an array of integers.
Quicksort, also known as partition-exchange sort, uses these steps.
Choose any element of the array to be the pivot.
Divide all other elements (except the pivot) into two partitions.
All elements less than the pivot must be in the first partition.
All elements greater than the pivot must be in the second partition.
Use recursion to sort both partitions.
Join the first sorted partition, the pivot, and the second sorted partition.
The best pivot creates partitions of equal length (or lengths differing by 1).
The worst pivot creates an empty partition (for example, if the pivot is the first or last element of a sorted array).
The run-time of Quicksort ranges from O(n log n) with the best pivots, to O(n2) with the worst pivots, where n is the number of elements in the array.
This is a simple quicksort algorithm, adapted from Wikipedia.
function quicksort(array)
less, equal, greater := three empty arrays
if length(array) > 1
pivot := select any element of array
for each x in array
if x < pivot then add x to less
if x = pivot then add x to equal
if x > pivot then add x to greater
quicksort(less)
quicksort(greater)
array := concatenate(less, equal, greater)
A better quicksort algorithm works in place, by swapping elements within the array, to avoid the memory allocation of more arrays.
function quicksort(array)
if length(array) > 1
pivot := select any element of array
left := first index of array
right := last index of array
while left ≤ right
while array[left] < pivot
left := left + 1
while array[right] > pivot
right := right - 1
if left ≤ right
swap array[left] with array[right]
left := left + 1
right := right - 1
quicksort(array from first index to right)
quicksort(array from left to last index)
Quicksort has a reputation as the fastest sort. Optimized variants of quicksort are common features of many languages and libraries. One often contrasts quicksort with merge sort, because both sorts have an average time of O(n log n).
"On average, mergesort does fewer comparisons than quicksort, so it may be better when complicated comparison routines are used. Mergesort also takes advantage of pre-existing order, so it would be favored for using sort() to merge several sorted arrays. On the other hand, quicksort is often faster for small arrays, and on arrays of a few distinct values, repeated many times." — http://perldoc.perl.org/sort.html
Quicksort is at one end of the spectrum of divide-and-conquer algorithms, with merge sort at the opposite end.
Quicksort is a conquer-then-divide algorithm, which does most of the work during the partitioning and the recursive calls. The subsequent reassembly of the sorted partitions involves trivial effort.
Merge sort is a divide-then-conquer algorithm. The partioning happens in a trivial way, by splitting the input array in half. Most of the work happens during the recursive calls and the merge phase.
With quicksort, every element in the first partition is less than or equal to every element in the second partition. Therefore, the merge phase of quicksort is so trivial that it needs no mention!
This task has not specified whether to allocate new arrays, or sort in place. This task also has not specified how to choose the pivot element. (Common ways to are to choose the first element, the middle element, or the median of three elements.) Thus there is a variety among the following implementations.
| #AutoHotkey | AutoHotkey | a := [4, 65, 2, -31, 0, 99, 83, 782, 7]
for k, v in QuickSort(a)
Out .= "," v
MsgBox, % SubStr(Out, 2)
return
QuickSort(a)
{
if (a.MaxIndex() <= 1)
return a
Less := [], Same := [], More := []
Pivot := a[1]
for k, v in a
{
if (v < Pivot)
less.Insert(v)
else if (v > Pivot)
more.Insert(v)
else
same.Insert(v)
}
Less := QuickSort(Less)
Out := QuickSort(More)
if (Same.MaxIndex())
Out.Insert(1, Same*) ; insert all values of same at index 1
if (Less.MaxIndex())
Out.Insert(1, Less*) ; insert all values of less at index 1
return Out
} |
http://rosettacode.org/wiki/Sorting_algorithms/Patience_sort | Sorting algorithms/Patience sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Sort an array of numbers (of any convenient size) into ascending order using Patience sorting.
Related task
Longest increasing subsequence
| #JavaScript | JavaScript | const patienceSort = (nums) => {
const piles = []
for (let i = 0; i < nums.length; i++) {
const num = nums[i]
const destinationPileIndex = piles.findIndex(
(pile) => num >= pile[pile.length - 1]
)
if (destinationPileIndex === -1) {
piles.push([num])
} else {
piles[destinationPileIndex].push(num)
}
}
for (let i = 0; i < nums.length; i++) {
let destinationPileIndex = 0
for (let p = 1; p < piles.length; p++) {
const pile = piles[p]
if (pile[0] < piles[destinationPileIndex][0]) {
destinationPileIndex = p
}
}
const distPile = piles[destinationPileIndex]
nums[i] = distPile.shift()
if (distPile.length === 0) {
piles.splice(destinationPileIndex, 1)
}
}
return nums
}
console.log(patienceSort([10,6,-30,9,18,1,-20]));
|
http://rosettacode.org/wiki/Sorting_algorithms/Insertion_sort | Sorting algorithms/Insertion sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
This page uses content from Wikipedia. The original article was at Insertion sort. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
An O(n2) sorting algorithm which moves elements one at a time into the correct position.
The algorithm consists of inserting one element at a time into the previously sorted part of the array, moving higher ranked elements up as necessary.
To start off, the first (or smallest, or any arbitrary) element of the unsorted array is considered to be the sorted part.
Although insertion sort is an O(n2) algorithm, its simplicity, low overhead, good locality of reference and efficiency make it a good choice in two cases:
small n,
as the final finishing-off algorithm for O(n logn) algorithms such as mergesort and quicksort.
The algorithm is as follows (from wikipedia):
function insertionSort(array A)
for i from 1 to length[A]-1 do
value := A[i]
j := i-1
while j >= 0 and A[j] > value do
A[j+1] := A[j]
j := j-1
done
A[j+1] = value
done
Writing the algorithm for integers will suffice.
| #AppleScript | AppleScript | -- In-place insertion sort
on insertionSort(theList, l, r) -- Sort items l thru r of theList.
set listLength to (count theList)
if (listLength < 2) then return
-- Convert negative and/or transposed range indices.
if (l < 0) then set l to listLength + l + 1
if (r < 0) then set r to listLength + r + 1
if (l > r) then set {l, r} to {r, l}
-- The list as a script property to allow faster references to its items.
script o
property lst : theList
end script
-- Set up a minor optimisation whereby the latest instance of the highest value so far isn't
-- put back into the list until either it's superseded or the end of the sort is reached.
set highestSoFar to o's lst's item l
set rv to o's lst's item (l + 1)
if (highestSoFar > rv) then
set o's lst's item l to rv
else
set highestSoFar to rv
end if
-- Work through the rest of the range, rotating values back into the sorted group as necessary.
repeat with j from (l + 2) to r
set rv to o's lst's item j
if (highestSoFar > rv) then
repeat with i from (j - 2) to l by -1
set lv to o's lst's item i
if (lv > rv) then
set o's lst's item (i + 1) to lv
else
set i to i + 1
exit repeat
end if
end repeat
set o's lst's item i to rv
else
set o's lst's item (j - 1) to highestSoFar
set highestSoFar to rv
end if
end repeat
set o's lst's item r to highestSoFar
return -- nothing.
end insertionSort
property sort : insertionSort
-- Demo:
local aList
set aList to {60, 73, 11, 66, 6, 77, 41, 97, 59, 45, 64, 15, 91, 100, 22, 89, 77, 59, 54, 61}
sort(aList, 1, -1) -- Sort items 1 thru -1 of aList.
return aList |
http://rosettacode.org/wiki/Sorting_algorithms/Permutation_sort | Sorting algorithms/Permutation sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Implement a permutation sort, which proceeds by generating the possible permutations
of the input array/list until discovering the sorted one.
Pseudocode:
while not InOrder(list) do
nextPermutation(list)
done
| #Phix | Phix | with javascript_semantics
function inOrder(sequence s)
for i=2 to length(s) do
if s[i]<s[i-1] then return false end if
end for
return true
end function
function permutationSort(sequence s)
for n=1 to factorial(length(s)) do
sequence perm = permute(n,s)
if inOrder(perm) then return perm end if
end for
?9/0 -- should never happen
end function
?permutationSort({"dog",0,15.545,{"cat","pile","abcde",1},"cat"})
|
http://rosettacode.org/wiki/Sorting_algorithms/Permutation_sort | Sorting algorithms/Permutation sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Implement a permutation sort, which proceeds by generating the possible permutations
of the input array/list until discovering the sorted one.
Pseudocode:
while not InOrder(list) do
nextPermutation(list)
done
| #PHP | PHP | function inOrder($arr){
for($i=0;$i<count($arr);$i++){
if(isset($arr[$i+1])){
if($arr[$i] > $arr[$i+1]){
return false;
}
}
}
return true;
}
function permute($items, $perms = array( )) {
if (empty($items)) {
if(inOrder($perms)){
return $perms;
}
} else {
for ($i = count($items) - 1; $i >= 0; --$i) {
$newitems = $items;
$newperms = $perms;
list($foo) = array_splice($newitems, $i, 1);
array_unshift($newperms, $foo);
$res = permute($newitems, $newperms);
if($res){
return $res;
}
}
}
}
$arr = array( 8, 3, 10, 6, 1, 9, 7, 2, 5, 4);
$arr = permute($arr);
echo implode(',',$arr); |
http://rosettacode.org/wiki/Sorting_algorithms/Merge_sort | Sorting algorithms/Merge sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
The merge sort is a recursive sort of order n*log(n).
It is notable for having a worst case and average complexity of O(n*log(n)), and a best case complexity of O(n) (for pre-sorted input).
The basic idea is to split the collection into smaller groups by halving it until the groups only have one element or no elements (which are both entirely sorted groups).
Then merge the groups back together so that their elements are in order.
This is how the algorithm gets its divide and conquer description.
Task
Write a function to sort a collection of integers using the merge sort.
The merge sort algorithm comes in two parts:
a sort function and
a merge function
The functions in pseudocode look like this:
function mergesort(m)
var list left, right, result
if length(m) ≤ 1
return m
else
var middle = length(m) / 2
for each x in m up to middle - 1
add x to left
for each x in m at and after middle
add x to right
left = mergesort(left)
right = mergesort(right)
if last(left) ≤ first(right)
append right to left
return left
result = merge(left, right)
return result
function merge(left,right)
var list result
while length(left) > 0 and length(right) > 0
if first(left) ≤ first(right)
append first(left) to result
left = rest(left)
else
append first(right) to result
right = rest(right)
if length(left) > 0
append rest(left) to result
if length(right) > 0
append rest(right) to result
return result
See also
the Wikipedia entry: merge sort
Note: better performance can be expected if, rather than recursing until length(m) ≤ 1, an insertion sort is used for length(m) smaller than some threshold larger than 1. However, this complicates the example code, so it is not shown here.
| #11l | 11l | F merge(left, right)
[Int] result
V left_idx = 0
V right_idx = 0
L left_idx < left.len & right_idx < right.len
I left[left_idx] <= right[right_idx]
result.append(left[left_idx])
left_idx++
E
result.append(right[right_idx])
right_idx++
I left_idx < left.len
result.extend(left[left_idx ..])
I right_idx < right.len
result.extend(right[right_idx ..])
R result
F merge_sort(m)
I m.len <= 1
R m
V middle = m.len I/ 2
V left = m[0.<middle]
V right = m[middle..]
left = merge_sort(left)
right = merge_sort(right)
R Array(merge(left, right))
V arr = [7, 6, 5, 9, 8, 4, 3, 1, 2, 0]
print(merge_sort(arr)) |
http://rosettacode.org/wiki/Sorting_algorithms/Pancake_sort | Sorting algorithms/Pancake sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Task
Sort an array of integers (of any convenient size) into ascending order using Pancake sorting.
In short, instead of individual elements being sorted, the only operation allowed is to "flip" one end of the list, like so:
Before: 6 7 8 9 2 5 3 4 1
After: 9 8 7 6 2 5 3 4 1
Only one end of the list can be flipped; this should be the low end, but the high end is okay if it's easier to code or works better, but it must be the same end for the entire solution. (The end flipped can't be arbitrarily changed.)
Show both the initial, unsorted list and the final sorted list.
(Intermediate steps during sorting are optional.)
Optimizations are optional (but recommended).
Related tasks
Number reversal game
Topswops
Also see
Wikipedia article: pancake sorting.
| #FreeBASIC | FreeBASIC | ' version 11-04-2017
' compile with: fbc -s console
' for boundry checks on array's compile with: fbc -s console -exx
' direction = 1, (default) sort ascending
' direction <> 1 sort descending
' show = 0, (default) do not show sorting
' show <> 0, show sorting
Sub pancake_sort(a() As Long,direction As Long = 1, show As Long = 0)
' array's can have subscript range from -2147483648 to +2147483647
Dim As Long i, j, n
Dim As Long lb = LBound(a)
Dim As Long ub = UBound(a)
If show <> 0 Then ' show initial state
For j = lb To ub
Print Using "####"; a(j);
Next
Print
End If
For i = ub To lb +1 Step -1
n = lb
For j = lb +1 To i
If direction = 1 Then
If a(n) < a(j) Then n = j
Else
If a(n) > a(j) Then n = j
End If
Next
If n < i Then
If n > lb Then
For j = lb To lb + ((n - lb) \ 2)
Swap a(j), a(lb + n - j)
Next
If show <> 0 Then
For j = lb To ub
Print Using "####"; a(j);
Next
Print
End If
End If
For j = lb To lb + ((i - lb) \ 2)
Swap a(j), a(lb + i - j)
Next
If show <> 0 Then
For j = lb To ub
Print Using "####"; a(j);
Next
Print
End If
End If
Next
End Sub
' ------=< MAIN >=------
Dim As Long i, array(-7 To 7)
Dim As Long lb = LBound(array)
Dim As Long ub = UBound(array)
Randomize Timer
For i = lb To ub : array(i) = i : Next
For i = lb To ub ' little shuffle
Swap array(i), array(Int(Rnd * (ub - lb +1) + lb))
Next
Print "unsorted ";
For i = lb To ub
Print Using "####"; array(i);
Next
Print : Print
pancake_sort(array())
Print " sorted ";
For i = lb To ub
Print Using "####"; array(i);
Next
Print : Print
Dim As Long l(10 To ...) = {0, -30, 20, -10, 0, 10, -20}
pancake_sort(l(),0,1) ' sort array l, ascending and show process
Print : Print " sorted l()";
For i = LBound(l) To UBound(l)
Print Using "####"; l(i);
Next
Print
' empty keyboard buffer
While Inkey <> "" : Wend
Print : Print "hit any key to end program"
Sleep
End |
http://rosettacode.org/wiki/Sorting_algorithms/Stooge_sort | Sorting algorithms/Stooge sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
This page uses content from Wikipedia. The original article was at Stooge sort. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Show the Stooge Sort for an array of integers.
The Stooge Sort algorithm is as follows:
algorithm stoogesort(array L, i = 0, j = length(L)-1)
if L[j] < L[i] then
L[i] ↔ L[j]
if j - i > 1 then
t := (j - i + 1)/3
stoogesort(L, i , j-t)
stoogesort(L, i+t, j )
stoogesort(L, i , j-t)
return L
| #ooRexx | ooRexx | /* Rexx */
call demo
return
exit
-- -----------------------------------------------------------------------------
-- Stooge sort implementation
-- -----------------------------------------------------------------------------
::routine stoogeSort
use arg rL_, i_ = 0, j_ = .nil
if j_ = .nil then j_ = rL_~items() - 1
if rL_~get(j_) < rL_~get(i_) then do
Lt = rL_~get(i_)
rL_~set(i_, rL_~get(j_))
rL_~set(j_, Lt)
end
if j_ - i_ > 1 then do
t_ = (j_ - i_ + 1) % 3
rL_ = stoogeSort(rL_, i_, j_ - t_)
rL_ = stoogeSort(rL_, i_ + t_, j_)
rL_ = stoogeSort(rL_, i_, j_ - t_)
end
return rL_
-- -----------------------------------------------------------------------------
-- Demonstrate the implementation
-- -----------------------------------------------------------------------------
::routine demo
iList = .nlist~of(1, 4, 5, 3, -6, 3, 7, 10, -2, -5, 7, 5, 9, -3, 7)
sList = iList~copy()
placesList = .nlist~of( -
"UK London", "US New York", "US Boston", "US Washington" -
, "UK Washington", "US Birmingham", "UK Birmingham", "UK Boston" -
)
sList = stoogeSort(sList)
sortedList = stoogeSort(placesList~copy())
iLists = .list~of(iList, sList)
loop ln = 0 to iLists~items() - 1
icl = iLists[ln]
rpt = ''
loop ct = 0 to icl~items() - 1
rpt = rpt icl[ct]
end ct
say '['rpt~strip()~changestr(' ', ',')']'
end ln
say
sLists = .list~of(placesList, sortedList)
loop ln = 0 to sLists~items() - 1
scl = sLists[ln]
loop ct = 0 to scl~items() - 1
say right(ct + 1, 3)':' scl[ct]
end ct
say
end ln
return
-- -----------------------------------------------------------------------------
-- Helper class. Map get and set methods for easier conversion from java.util.List
-- -----------------------------------------------------------------------------
::class NList mixinclass List public
-- Map get() to at()
::method get
use arg ix
return self~at(ix)
-- Map set() to put()
::method set
use arg ix, item
self~put(item, ix)
return
|
http://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort | Sorting algorithms/Sleep sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
In general, sleep sort works by starting a separate task for each item to be sorted, where each task sleeps for an interval corresponding to the item's sort key, then emits the item. Items are then collected sequentially in time.
Task: Write a program that implements sleep sort. Have it accept non-negative integers on the command line and print the integers in sorted order. If this is not idomatic in your language or environment, input and output may be done differently. Enhancements for optimization, generalization, practicality, robustness, and so on are not required.
Sleep sort was presented anonymously on 4chan and has been discussed on Hacker News.
| #Swift | Swift | import Foundation
for i in [5, 2, 4, 6, 1, 7, 20, 14] {
let time = dispatch_time(DISPATCH_TIME_NOW,
Int64(i * Int(NSEC_PER_SEC)))
dispatch_after(time, dispatch_get_main_queue()) {
print(i)
}
}
CFRunLoopRun() |
http://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort | Sorting algorithms/Sleep sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
In general, sleep sort works by starting a separate task for each item to be sorted, where each task sleeps for an interval corresponding to the item's sort key, then emits the item. Items are then collected sequentially in time.
Task: Write a program that implements sleep sort. Have it accept non-negative integers on the command line and print the integers in sorted order. If this is not idomatic in your language or environment, input and output may be done differently. Enhancements for optimization, generalization, practicality, robustness, and so on are not required.
Sleep sort was presented anonymously on 4chan and has been discussed on Hacker News.
| #Tcl | Tcl | #!/bin/env tclsh
set count 0
proc process val {
puts $val
incr ::count
}
# Schedule the output of the values
foreach val $argv {
after [expr {$val * 10}] [list process $val]
}
# Run event loop until all values output...
while {$count < $argc} {
vwait count
} |
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