task_url
stringlengths 30
116
| task_name
stringlengths 2
86
| task_description
stringlengths 0
14.4k
| language_url
stringlengths 2
53
| language_name
stringlengths 1
52
| code
stringlengths 0
61.9k
|
---|---|---|---|---|---|
http://rosettacode.org/wiki/Execute_SNUSP | Execute SNUSP | Execute SNUSP is an implementation of SNUSP.
Other implementations of SNUSP.
RCSNUSP
SNUSP
An implementation need only properly implement the Core SNUSP instructions ('$', '\', '/', '+', '-', '<', '>', ',', '.', '!', and '?'). Modular SNUSP ('#', '@') and Bloated SNUSP (':', ';', '%', and '&') are also allowed, but not required. Any extra characters that you implement should be noted in the description of your implementation. Any cell size is allowed, EOF support is optional, as is whether you have bounded or unbounded memory.
| #Lua | Lua | import strutils
# Requires 5 bytes of data store.
const Hw = r"""
/++++!/===========?\>++.>+.+++++++..+++\
\+++\ | /+>+++++++>/ /++++++++++<<.++>./
$+++/ | \+++++++++>\ \+++++.>.+++.-----\
\==-<<<<+>+++/ /=.>.+>.--------.-/"""
#---------------------------------------------------------------------------------------------------
proc snusp(dsLen: int; code: string) =
## The interpreter.
var
ds = newSeq[byte](dsLen) # Data store.
dp = 0 # Data pointer.
cs = code.splitLines() # Two dimensional code store.
ipr, ipc = 0 # Instruction pointers in row ans column.
dir = 0 # Direction (0 = right, 1 = down, 2 = left, 3 = up).
# Initialize instruction pointers.
for r, row in cs:
ipc = row.find('$')
if ipc >= 0:
ipr = r
break
#.................................................................................................
func step() =
## Update the instruction pointers acccording to the direction.
if (dir and 1) == 0:
inc ipc, 1 - (dir and 2)
else:
inc ipr, 1 - (dir and 2)
#.................................................................................................
# Interpreter loop.
while ipr in 0..cs.high and ipc in 0..cs[ipr].high:
case cs[ipr][ipc]
of '>': inc dp
of '<': dec dp
of '+': inc ds[dp]
of '-': dec ds[dp]
of '.': stdout.write chr(ds[dp])
of ',': ds[dp] = byte(stdin.readLine()[0])
of '/': dir = not dir
of '\\': dir = dir xor 1
of '!': step()
of '?': (if ds[dp] == 0: step())
else: discard
step()
#———————————————————————————————————————————————————————————————————————————————————————————————————
when isMainModule:
snusp(5, Hw) |
http://rosettacode.org/wiki/Execute_SNUSP | Execute SNUSP | Execute SNUSP is an implementation of SNUSP.
Other implementations of SNUSP.
RCSNUSP
SNUSP
An implementation need only properly implement the Core SNUSP instructions ('$', '\', '/', '+', '-', '<', '>', ',', '.', '!', and '?'). Modular SNUSP ('#', '@') and Bloated SNUSP (':', ';', '%', and '&') are also allowed, but not required. Any extra characters that you implement should be noted in the description of your implementation. Any cell size is allowed, EOF support is optional, as is whether you have bounded or unbounded memory.
| #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | import strutils
# Requires 5 bytes of data store.
const Hw = r"""
/++++!/===========?\>++.>+.+++++++..+++\
\+++\ | /+>+++++++>/ /++++++++++<<.++>./
$+++/ | \+++++++++>\ \+++++.>.+++.-----\
\==-<<<<+>+++/ /=.>.+>.--------.-/"""
#---------------------------------------------------------------------------------------------------
proc snusp(dsLen: int; code: string) =
## The interpreter.
var
ds = newSeq[byte](dsLen) # Data store.
dp = 0 # Data pointer.
cs = code.splitLines() # Two dimensional code store.
ipr, ipc = 0 # Instruction pointers in row ans column.
dir = 0 # Direction (0 = right, 1 = down, 2 = left, 3 = up).
# Initialize instruction pointers.
for r, row in cs:
ipc = row.find('$')
if ipc >= 0:
ipr = r
break
#.................................................................................................
func step() =
## Update the instruction pointers acccording to the direction.
if (dir and 1) == 0:
inc ipc, 1 - (dir and 2)
else:
inc ipr, 1 - (dir and 2)
#.................................................................................................
# Interpreter loop.
while ipr in 0..cs.high and ipc in 0..cs[ipr].high:
case cs[ipr][ipc]
of '>': inc dp
of '<': dec dp
of '+': inc ds[dp]
of '-': dec ds[dp]
of '.': stdout.write chr(ds[dp])
of ',': ds[dp] = byte(stdin.readLine()[0])
of '/': dir = not dir
of '\\': dir = dir xor 1
of '!': step()
of '?': (if ds[dp] == 0: step())
else: discard
step()
#———————————————————————————————————————————————————————————————————————————————————————————————————
when isMainModule:
snusp(5, Hw) |
http://rosettacode.org/wiki/Execute_SNUSP | Execute SNUSP | Execute SNUSP is an implementation of SNUSP.
Other implementations of SNUSP.
RCSNUSP
SNUSP
An implementation need only properly implement the Core SNUSP instructions ('$', '\', '/', '+', '-', '<', '>', ',', '.', '!', and '?'). Modular SNUSP ('#', '@') and Bloated SNUSP (':', ';', '%', and '&') are also allowed, but not required. Any extra characters that you implement should be noted in the description of your implementation. Any cell size is allowed, EOF support is optional, as is whether you have bounded or unbounded memory.
| #Nim | Nim | import strutils
# Requires 5 bytes of data store.
const Hw = r"""
/++++!/===========?\>++.>+.+++++++..+++\
\+++\ | /+>+++++++>/ /++++++++++<<.++>./
$+++/ | \+++++++++>\ \+++++.>.+++.-----\
\==-<<<<+>+++/ /=.>.+>.--------.-/"""
#---------------------------------------------------------------------------------------------------
proc snusp(dsLen: int; code: string) =
## The interpreter.
var
ds = newSeq[byte](dsLen) # Data store.
dp = 0 # Data pointer.
cs = code.splitLines() # Two dimensional code store.
ipr, ipc = 0 # Instruction pointers in row ans column.
dir = 0 # Direction (0 = right, 1 = down, 2 = left, 3 = up).
# Initialize instruction pointers.
for r, row in cs:
ipc = row.find('$')
if ipc >= 0:
ipr = r
break
#.................................................................................................
func step() =
## Update the instruction pointers acccording to the direction.
if (dir and 1) == 0:
inc ipc, 1 - (dir and 2)
else:
inc ipr, 1 - (dir and 2)
#.................................................................................................
# Interpreter loop.
while ipr in 0..cs.high and ipc in 0..cs[ipr].high:
case cs[ipr][ipc]
of '>': inc dp
of '<': dec dp
of '+': inc ds[dp]
of '-': dec ds[dp]
of '.': stdout.write chr(ds[dp])
of ',': ds[dp] = byte(stdin.readLine()[0])
of '/': dir = not dir
of '\\': dir = dir xor 1
of '!': step()
of '?': (if ds[dp] == 0: step())
else: discard
step()
#———————————————————————————————————————————————————————————————————————————————————————————————————
when isMainModule:
snusp(5, Hw) |
http://rosettacode.org/wiki/Execute_SNUSP | Execute SNUSP | Execute SNUSP is an implementation of SNUSP.
Other implementations of SNUSP.
RCSNUSP
SNUSP
An implementation need only properly implement the Core SNUSP instructions ('$', '\', '/', '+', '-', '<', '>', ',', '.', '!', and '?'). Modular SNUSP ('#', '@') and Bloated SNUSP (':', ';', '%', and '&') are also allowed, but not required. Any extra characters that you implement should be noted in the description of your implementation. Any cell size is allowed, EOF support is optional, as is whether you have bounded or unbounded memory.
| #OCaml | OCaml | with javascript_semantics
integer id = 0, ipr = 1, ipc = 1
procedure step()
if and_bits(id,1) == 0 then
ipc += 1 - and_bits(id,2)
else
ipr += 1 - and_bits(id,2)
end if
end procedure
procedure snusp(integer dlen, string s)
sequence ds = repeat(0,dlen) -- data store
integer dp = 1 -- data pointer
-- remove leading '\n' from string if present
s = trim_head(s,'\n')
-- make 2 dimensional instruction store and set instruction pointers
sequence cs = split(s,'\n')
ipr = 1
ipc = 1
-- look for starting instruction
for i=1 to length(cs) do
ipc = find('$',cs[i])
if ipc then
ipr = i
exit
end if
end for
id = 0
-- execute
while ipr>=1 and ipr<=length(cs)
and ipc>=1 and ipc<=length(cs[ipr]) do
integer op = cs[ipr][ipc]
switch op do
case '>' : dp += 1
case '<' : dp -= 1
case '+' : ds[dp] += 1
case '-' : ds[dp] -= 1
case '.' : puts(1,ds[dp])
case ',' : ds[dp] = getc(0)
case '/' : id = not_bits(id)
case '\\': id = xor_bits(id,1)
case '!' : step()
case '?' : if ds[dp]=0 then step() end if
end switch
step()
end while
end procedure
constant hw = """
/++++!/===========?\>++.>+.+++++++..+++\
\+++\ | /+>+++++++>/ /++++++++++<<.++>./
$+++/ | \+++++++++>\ \+++++.>.+++.-----\
\==-<<<<+>+++/ /=.>.+>.--------.-/"""
snusp(5, hw)
|
http://rosettacode.org/wiki/Extend_your_language | Extend your language | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other languages go much further. Most notably in the Forth and Lisp families, programming per se is done by extending the language without any formal distinction between built-in and user-defined elements.
If your language supports it, show how to introduce a new flow control mechanism. A practical and useful example is a four-way branch:
Occasionally, code must be written that depends on two conditions, resulting in up to four branches (depending on whether both, only the first, only the second, or none of the conditions are "true"). In a C-like language this could look like the following:
if (condition1isTrue) {
if (condition2isTrue)
bothConditionsAreTrue();
else
firstConditionIsTrue();
}
else if (condition2isTrue)
secondConditionIsTrue();
else
noConditionIsTrue();
Besides being rather cluttered, the statement(s) for 'condition2isTrue' must be written down twice. If 'condition2isTrue' were a lengthy and involved expression, it would be quite unreadable, and the code generated by the compiler might be unnecessarily large.
This can be improved by introducing a new keyword if2. It is similar to if, but takes two conditional statements instead of one, and up to three 'else' statements. One proposal (in pseudo-C syntax) might be:
if2 (condition1isTrue) (condition2isTrue)
bothConditionsAreTrue();
else1
firstConditionIsTrue();
else2
secondConditionIsTrue();
else
noConditionIsTrue();
Pick the syntax which suits your language. The keywords 'else1' and 'else2' are just examples. The new conditional expression should look, nest and behave analogously to the language's built-in 'if' statement.
| #Go | Go | package main
import "fmt"
type F func()
type If2 struct {cond1, cond2 bool}
func (i If2) else1(f F) If2 {
if i.cond1 && !i.cond2 {
f()
}
return i
}
func (i If2) else2(f F) If2 {
if i.cond2 && !i.cond1 {
f()
}
return i
}
func (i If2) else0(f F) If2 {
if !i.cond1 && !i.cond2 {
f()
}
return i
}
func if2(cond1, cond2 bool, f F) If2 {
if cond1 && cond2 {
f()
}
return If2{cond1, cond2}
}
func main() {
a, b := 0, 1
if2 (a == 1, b == 3, func() {
fmt.Println("a = 1 and b = 3")
}).else1 (func() {
fmt.Println("a = 1 and b <> 3")
}).else2 (func() {
fmt.Println("a <> 1 and b = 3")
}).else0 (func() {
fmt.Println("a <> 1 and b <> 3")
})
// It's also possible to omit any (or all) of the 'else' clauses or to call them out of order
a, b = 1, 0
if2 (a == 1, b == 3, func() {
fmt.Println("a = 1 and b = 3")
}).else0 (func() {
fmt.Println("a <> 1 and b <> 3")
}).else1 (func() {
fmt.Println("a = 1 and b <> 3")
})
} |
http://rosettacode.org/wiki/Exponentiation_order | Exponentiation order | This task will demonstrate the order of exponentiation (xy) when there are multiple exponents.
(Many programming languages, especially those with extended─precision integer arithmetic, usually support one of **, ^, ↑ or some such for exponentiation.)
Task requirements
Show the result of a language's evaluation of multiple exponentiation (either as an integer or floating point).
If your language's exponentiation operator is not one of the usual ones, please comment on how to recognize it.
Using whatever operator or syntax your language supports (if any), show the results in three lines (with identification):
5**3**2
(5**3)**2
5**(3**2)
If there are other methods (or formats) of multiple exponentiations, show them as well.
See also
MathWorld entry: exponentiation
Related tasks
exponentiation operator
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #REXX | REXX | /*REXX program demonstrates various ways of multiple exponentiations. */
/*┌────────────────────────────────────────────────────────────────────┐
│ The REXX language uses ** for exponentiation. │
│ Also, * * can be used. │
| and even */*power of*/* |
└────────────────────────────────────────────────────────────────────┘*/
say ' 5**3**2 ───► ' 5**3**2
say ' (5**3)**2 ───► ' (5**3)**2
say ' 5**(3**2) ───► ' 5**(3**2)
/*stick a fork in it, we're done.*/ |
http://rosettacode.org/wiki/Exponentiation_order | Exponentiation order | This task will demonstrate the order of exponentiation (xy) when there are multiple exponents.
(Many programming languages, especially those with extended─precision integer arithmetic, usually support one of **, ^, ↑ or some such for exponentiation.)
Task requirements
Show the result of a language's evaluation of multiple exponentiation (either as an integer or floating point).
If your language's exponentiation operator is not one of the usual ones, please comment on how to recognize it.
Using whatever operator or syntax your language supports (if any), show the results in three lines (with identification):
5**3**2
(5**3)**2
5**(3**2)
If there are other methods (or formats) of multiple exponentiations, show them as well.
See also
MathWorld entry: exponentiation
Related tasks
exponentiation operator
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #Ring | Ring |
see "(5^3)^2 =>" + pow(pow(5,3),2) + nl
see "5^(3^2) =>" + pow(5,pow(3,2)) + nl
|
http://rosettacode.org/wiki/Exponentiation_order | Exponentiation order | This task will demonstrate the order of exponentiation (xy) when there are multiple exponents.
(Many programming languages, especially those with extended─precision integer arithmetic, usually support one of **, ^, ↑ or some such for exponentiation.)
Task requirements
Show the result of a language's evaluation of multiple exponentiation (either as an integer or floating point).
If your language's exponentiation operator is not one of the usual ones, please comment on how to recognize it.
Using whatever operator or syntax your language supports (if any), show the results in three lines (with identification):
5**3**2
(5**3)**2
5**(3**2)
If there are other methods (or formats) of multiple exponentiations, show them as well.
See also
MathWorld entry: exponentiation
Related tasks
exponentiation operator
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #Ruby | Ruby | ar = ["5**3**2", "(5**3)**2", "5**(3**2)", "[5,3,2].inject(:**)"]
ar.each{|exp| puts "#{exp}:\t#{eval exp}"}
|
http://rosettacode.org/wiki/Filter | Filter | Task
Select certain elements from an Array into a new Array in a generic way.
To demonstrate, select all even numbers from an Array.
As an option, give a second solution which filters destructively,
by modifying the original Array rather than creating a new Array.
| #zkl | zkl | T(1,4,9,16,25,36,"37",49,64,81,100, True,self)
.filter(fcn(n){(0).isType(n) and n.isOdd})
//-->L(1,9,25,49,81) |
http://rosettacode.org/wiki/FizzBuzz | FizzBuzz | Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuzz (instead of the number)
The FizzBuzz problem was presented as the lowest level of comprehension required to illustrate adequacy.
Also see
(a blog) dont-overthink-fizzbuzz
(a blog) fizzbuzz-the-programmers-stairway-to-heaven
| #Raku | Raku | for 1 .. 100 {
when $_ %% (3 & 5) { say 'FizzBuzz'; }
when $_ %% 3 { say 'Fizz'; }
when $_ %% 5 { say 'Buzz'; }
default { .say; }
} |
http://rosettacode.org/wiki/Extensible_prime_generator | Extensible prime generator | Task
Write a generator of prime numbers, in order, that will automatically adjust to accommodate the generation of any reasonably high prime.
The routine should demonstrably rely on either:
Being based on an open-ended counter set to count without upper limit other than system or programming language limits. In this case, explain where this counter is in the code.
Being based on a limit that is extended automatically. In this case, choose a small limit that ensures the limit will be passed when generating some of the values to be asked for below.
If other methods of creating an extensible prime generator are used, the algorithm's means of extensibility/lack of limits should be stated.
The routine should be used to:
Show the first twenty primes.
Show the primes between 100 and 150.
Show the number of primes between 7,700 and 8,000.
Show the 10,000th prime.
Show output on this page.
Note: You may reference code already on this site if it is written to be imported/included, then only the code necessary for import and the performance of this task need be shown. (It is also important to leave a forward link on the referenced tasks entry so that later editors know that the code is used for multiple tasks).
Note 2: If a languages in-built prime generator is extensible or is guaranteed to generate primes up to a system limit, (231 or memory overflow for example), then this may be used as long as an explanation of the limits of the prime generator is also given. (Which may include a link to/excerpt from, language documentation).
Note 3:The task is written so it may be useful in solving the task Emirp primes as well as others (depending on its efficiency).
Reference
Prime Numbers. Website with large count of primes.
| #Icon_and_Unicon | Icon and Unicon | ![2,3,5,7] | (nc := 11) | (nc +:= |wheel2345) |
http://rosettacode.org/wiki/Fibonacci_sequence | Fibonacci sequence | The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are generally considered too slow and are mostly used as an exercise in recursion).
The sequence is sometimes extended into negative numbers by using a straightforward inverse of the positive definition:
Fn = Fn+2 - Fn+1, if n<0
support for negative n in the solution is optional.
Related tasks
Fibonacci n-step number sequences
Leonardo numbers
References
Wikipedia, Fibonacci number
Wikipedia, Lucas number
MathWorld, Fibonacci Number
Some identities for r-Fibonacci numbers
OEIS Fibonacci numbers
OEIS Lucas numbers
| #Hoon | Hoon | |= n=@ud
=/ a=@ud 0
=/ b=@ud 1
|-
?: =(n 0) a
$(a b, b (add a b), n (dec n)) |
http://rosettacode.org/wiki/Factors_of_an_integer | Factors of an integer |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |
Comparison |
Matching
Memory Operations
Pointers & references |
Addresses
Task
Compute the factors of a positive integer.
These factors are the positive integers by which the number being factored can be divided to yield a positive integer result.
(Though the concepts function correctly for zero and negative integers, the set of factors of zero has countably infinite members, and the factors of negative integers can be obtained from the factors of related positive numbers without difficulty; this task does not require handling of either of these cases).
Note that every prime number has two factors: 1 and itself.
Related tasks
count in factors
prime decomposition
Sieve of Eratosthenes
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
sequence: smallest number greater than previous term with exactly n divisors
| #Raku | Raku | sub factors (Int $n) { (1..$n).grep($n %% *) } |
http://rosettacode.org/wiki/Execute_HQ9%2B | Execute HQ9+ | Task
Implement a HQ9+ interpreter or compiler.
| #Common_Lisp | Common Lisp | import std.stdio, std.string;
void main(in string[] args) {
if (args.length != 2 ||
args[1].length != args[1].countchars("hHqQ9+")) {
writeln("Not valid HQ9+ code.");
return;
}
ulong accumulator;
foreach (immutable c; args[1]) {
final switch(c) {
case 'Q', 'q':
writeln(args[1]);
break;
case 'H', 'h':
writeln("Hello, world!");
break;
case '9':
int bottles = 99;
while (bottles > 1) {
writeln(bottles, " bottles of beer on the wall,");
writeln(bottles, " bottles of beer.");
writeln("Take one down, pass it around,");
if (--bottles > 1)
writeln(bottles,
" bottles of beer on the wall.\n");
}
writeln("1 bottle of beer on the wall.\n");
break;
case '+':
accumulator++;
break;
}
}
} |
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call | Exceptions/Catch an exception thrown in a nested call | Show how to create a user-defined exception and show how to catch an exception raised from several nested calls away.
Create two user-defined exceptions, U0 and U1.
Have function foo call function bar twice.
Have function bar call function baz.
Arrange for function baz to raise, or throw exception U0 on its first call, then exception U1 on its second.
Function foo should catch only exception U0, not U1.
Show/describe what happens when the program is run.
| #ALGOL_68 | ALGOL 68 | MODE OBJ = STRUCT(
INT value,
STRUCT(
STRING message,
FLEX[0]STRING args,
PROC(REF OBJ)BOOL u0, u1
) exception
);
PROC on u0 = (REF OBJ self, PROC (REF OBJ) BOOL mended)VOID:
u0 OF exception OF self := mended;
PROC on u1 = (REF OBJ self, PROC (REF OBJ) BOOL mended)VOID:
u1 OF exception OF self := mended;
PRIO INIT = 1, RAISE = 1;
OP INIT = (REF OBJ self, INT value)REF OBJ: (
value OF self := value;
u0 OF exception OF self := u1 OF exception OF self := (REF OBJ skip)BOOL: FALSE;
args OF exception OF self := message OF exception OF self := "OBJ Exception";
self
);
OP RAISE = (REF OBJ self, PROC (REF OBJ) BOOL mended)VOID:
IF NOT mended(self) THEN
put(stand error, (message OF exception OF self+" not caught - stop", new line));
stop
FI;
PROC (REF OBJ)VOID bar, baz; # early declaration is required by the ALGOL 68RS subset language #
PROC foo := VOID:(
FOR value FROM 0 TO 1 DO
REF OBJ i = LOC OBJ INIT value;
on u0(i, (REF OBJ skip)BOOL: (GO TO except u0; SKIP ));
bar(i);
GO TO end on u0;
except u0:
print(("Function foo caught exception u0", new line));
end on u0: SKIP
OD
);
# PROC # bar := (REF OBJ i)VOID:(
baz(i) # Nest those calls #
);
# PROC # baz := (REF OBJ i)VOID:
IF value OF i = 0 THEN
i RAISE u0 OF exception OF i
ELSE
i RAISE u1 OF exception OF i
FI;
foo |
http://rosettacode.org/wiki/Execute_a_system_command | Execute a system command | Task
Run either the ls system command (dir on Windows), or the pause system command.
Related task
Get system command output
| #ABAP | ABAP | *&---------------------------------------------------------------------*
*& Report ZEXEC_SYS_CMD
*&
*&---------------------------------------------------------------------*
*&
*&
*&---------------------------------------------------------------------*
REPORT zexec_sys_cmd.
DATA: lv_opsys TYPE syst-opsys,
lt_sxpgcotabe TYPE TABLE OF sxpgcotabe,
ls_sxpgcotabe LIKE LINE OF lt_sxpgcotabe,
ls_sxpgcolist TYPE sxpgcolist,
lv_name TYPE sxpgcotabe-name,
lv_opcommand TYPE sxpgcotabe-opcommand,
lv_index TYPE c,
lt_btcxpm TYPE TABLE OF btcxpm,
ls_btcxpm LIKE LINE OF lt_btcxpm
.
* Initialize
lv_opsys = sy-opsys.
CLEAR lt_sxpgcotabe[].
IF lv_opsys EQ 'Windows NT'.
lv_opcommand = 'dir'.
ELSE.
lv_opcommand = 'ls'.
ENDIF.
* Check commands
SELECT * FROM sxpgcotabe INTO TABLE lt_sxpgcotabe
WHERE opsystem EQ lv_opsys
AND opcommand EQ lv_opcommand.
IF lt_sxpgcotabe IS INITIAL.
CLEAR ls_sxpgcolist.
CLEAR lv_name.
WHILE lv_name IS INITIAL.
* Don't mess with other users' commands
lv_index = sy-index.
CONCATENATE 'ZLS' lv_index INTO lv_name.
SELECT * FROM sxpgcostab INTO ls_sxpgcotabe
WHERE name EQ lv_name.
ENDSELECT.
IF sy-subrc = 0.
CLEAR lv_name.
ENDIF.
ENDWHILE.
ls_sxpgcolist-name = lv_name.
ls_sxpgcolist-opsystem = lv_opsys.
ls_sxpgcolist-opcommand = lv_opcommand.
* Create own ls command when nothing is declared
CALL FUNCTION 'SXPG_COMMAND_INSERT'
EXPORTING
command = ls_sxpgcolist
public = 'X'
EXCEPTIONS
command_already_exists = 1
no_permission = 2
parameters_wrong = 3
foreign_lock = 4
system_failure = 5
OTHERS = 6.
IF sy-subrc <> 0.
* Implement suitable error handling here
ELSE.
* Hooray it worked! Let's try to call it
CALL FUNCTION 'SXPG_COMMAND_EXECUTE_LONG'
EXPORTING
commandname = lv_name
TABLES
exec_protocol = lt_btcxpm
EXCEPTIONS
no_permission = 1
command_not_found = 2
parameters_too_long = 3
security_risk = 4
wrong_check_call_interface = 5
program_start_error = 6
program_termination_error = 7
x_error = 8
parameter_expected = 9
too_many_parameters = 10
illegal_command = 11
wrong_asynchronous_parameters = 12
cant_enq_tbtco_entry = 13
jobcount_generation_error = 14
OTHERS = 15.
IF sy-subrc <> 0.
* Implement suitable error handling here
WRITE: 'Cant execute ls - '.
CASE sy-subrc.
WHEN 1.
WRITE: / ' no permission!'.
WHEN 2.
WRITE: / ' command could not be created!'.
WHEN 3.
WRITE: / ' parameter list too long!'.
WHEN 4.
WRITE: / ' security risk!'.
WHEN 5.
WRITE: / ' wrong call of SXPG_COMMAND_EXECUTE_LONG!'.
WHEN 6.
WRITE: / ' command cant be started!'.
WHEN 7.
WRITE: / ' program terminated!'.
WHEN 8.
WRITE: / ' x_error!'.
WHEN 9.
WRITE: / ' parameter missing!'.
WHEN 10.
WRITE: / ' too many parameters!'.
WHEN 11.
WRITE: / ' illegal command!'.
WHEN 12.
WRITE: / ' wrong asynchronous parameters!'.
WHEN 13.
WRITE: / ' cant enqueue job!'.
WHEN 14.
WRITE: / ' cant create job!'.
WHEN 15.
WRITE: / ' unknown error!'.
WHEN OTHERS.
WRITE: / ' unknown error!'.
ENDCASE.
ELSE.
LOOP AT lt_btcxpm INTO ls_btcxpm.
WRITE: / ls_btcxpm.
ENDLOOP.
ENDIF.
ENDIF.
ENDIF. |
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterative or recursive.
Support for trapping negative n errors is optional.
Related task
Primorial numbers
| #AArch64_Assembly | AArch64 Assembly |
/* ARM assembly AARCH64 Raspberry PI 3B */
/* program factorial64.s */
/*******************************************/
/* Constantes file */
/*******************************************/
/* for this file see task include a file in language AArch64 assembly*/
.include "../includeConstantesARM64.inc"
/*********************************/
/* Initialized data */
/*********************************/
.data
szMessLargeNumber: .asciz "Number N to large. \n"
szMessNegNumber: .asciz "Number N is negative. \n"
szMessResult: .asciz "Resultat = @ \n" // message result
/*********************************/
/* UnInitialized data */
/*********************************/
.bss
sZoneConv: .skip 24
/*********************************/
/* code section */
/*********************************/
.text
.global main
main: // entry of program
mov x0,#-5
bl factorial
mov x0,#10
bl factorial
mov x0,#20
bl factorial
mov x0,#30
bl factorial
100: // standard end of the program
mov x0,0 // return code
mov x8,EXIT // request to exit program
svc 0 // perform the system call
/********************************************/
/* calculation */
/********************************************/
/* x0 contains number N */
factorial:
stp x1,lr,[sp,-16]! // save registers
cmp x0,#0
blt 99f
beq 100f
cmp x0,#1
beq 100f
bl calFactorial
cmp x0,#-1 // overflow ?
beq 98f
ldr x1,qAdrsZoneConv
bl conversion10
ldr x0,qAdrszMessResult
ldr x1,qAdrsZoneConv
bl strInsertAtCharInc // insert result at @ character
bl affichageMess // display message
b 100f
98: // display error message
ldr x0,qAdrszMessLargeNumber
bl affichageMess
b 100f
99: // display error message
ldr x0,qAdrszMessNegNumber
bl affichageMess
100:
ldp x1,lr,[sp],16 // restaur 2 registers
ret // return to address lr x30
qAdrszMessNegNumber: .quad szMessNegNumber
qAdrszMessLargeNumber: .quad szMessLargeNumber
qAdrsZoneConv: .quad sZoneConv
qAdrszMessResult: .quad szMessResult
/******************************************************************/
/* calculation */
/******************************************************************/
/* x0 contains the number N */
calFactorial:
cmp x0,1 // N = 1 ?
beq 100f // yes -> return
stp x20,lr,[sp,-16]! // save registers
mov x20,x0 // save N in x20
sub x0,x0,1 // call function with N - 1
bl calFactorial
cmp x0,-1 // error overflow ?
beq 99f // yes -> return
mul x10,x20,x0 // multiply result by N
umulh x11,x20,x0 // x11 is the hi rd if <> 0 overflow
cmp x11,0
mov x11,-1 // if overflow -1 -> x0
csel x0,x10,x11,eq // else x0 = x10
99:
ldp x20,lr,[sp],16 // restaur 2 registers
100:
ret // return to address lr x30
/********************************************************/
/* File Include fonctions */
/********************************************************/
/* for this file see task include a file in language AArch64 assembly */
.include "../includeARM64.inc"
|
http://rosettacode.org/wiki/Exponentiation_operator | Exponentiation operator | Most programming languages have a built-in implementation of exponentiation.
Task
Re-implement integer exponentiation for both intint and floatint as both a procedure, and an operator (if your language supports operator definition).
If the language supports operator (or procedure) overloading, then an overloaded form should be provided for both intint and floatint variants.
Related tasks
Exponentiation order
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #Chef | Chef | (defn ** [x n] (reduce * (repeat n x))) |
http://rosettacode.org/wiki/Exponentiation_operator | Exponentiation operator | Most programming languages have a built-in implementation of exponentiation.
Task
Re-implement integer exponentiation for both intint and floatint as both a procedure, and an operator (if your language supports operator definition).
If the language supports operator (or procedure) overloading, then an overloaded form should be provided for both intint and floatint variants.
Related tasks
Exponentiation order
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #Clojure | Clojure | (defn ** [x n] (reduce * (repeat n x))) |
http://rosettacode.org/wiki/Executable_library | Executable library | The general idea behind an executable library is to create a library
that when used as a library does one thing;
but has the ability to be run directly via command line.
Thus the API comes with a CLI in the very same source code file.
Task detail
Create a library/module/dll/shared object/... for a programming language that contains a function/method called hailstone that is a function taking a positive integer and returns the Hailstone sequence for that number.
The library, when executed directly should satisfy the remaining requirements of the Hailstone sequence task:
2. Use the routine to show that the hailstone sequence for the number 27 has 112 elements starting with 27, 82, 41, 124 and ending with 8, 4, 2, 1
3. Show the number less than 100,000 which has the longest hailstone sequence together with that sequence's length.
Create a second executable to calculate the following:
Use the library's hailstone function, in the standard manner, (or document how this use deviates from standard use of a library), together with extra code in this executable, to find the hailstone length returned most often for 1 ≤ n < 100,000.
Explain any extra setup/run steps needed to complete the task.
Notes:
It is assumed that for a language that overwhelmingly ships in a compiled form, such as C, the library must also be an executable and the compiled user of that library is to do so without changing the compiled library. I.e. the compile tool-chain is assumed not to be present in the runtime environment.
Interpreters are present in the runtime environment. | #Io | Io | HailStone := Object clone
HailStone sequence := method(n,
if(n < 1, Exception raise("hailstone: expect n >= 1 not #{n}" interpolate))
n = n floor // make sure integer value
stones := list(n)
while (n != 1,
n = if(n isEven, n/2, 3*n + 1)
stones append(n)
)
stones
)
if( isLaunchScript,
out := HailStone sequence(27)
writeln("hailstone(27) has length ",out size,": ",
out slice(0,4) join(" ")," ... ",out slice(-4) join(" "))
maxSize := 0
maxN := 0
for(n, 1, 100000-1,
out = HailStone sequence(n)
if(out size > maxSize,
maxSize = out size
maxN = n
)
)
writeln("For numbers < 100,000, ", maxN,
" has the longest sequence of ", maxSize, " elements.")
) |
http://rosettacode.org/wiki/Executable_library | Executable library | The general idea behind an executable library is to create a library
that when used as a library does one thing;
but has the ability to be run directly via command line.
Thus the API comes with a CLI in the very same source code file.
Task detail
Create a library/module/dll/shared object/... for a programming language that contains a function/method called hailstone that is a function taking a positive integer and returns the Hailstone sequence for that number.
The library, when executed directly should satisfy the remaining requirements of the Hailstone sequence task:
2. Use the routine to show that the hailstone sequence for the number 27 has 112 elements starting with 27, 82, 41, 124 and ending with 8, 4, 2, 1
3. Show the number less than 100,000 which has the longest hailstone sequence together with that sequence's length.
Create a second executable to calculate the following:
Use the library's hailstone function, in the standard manner, (or document how this use deviates from standard use of a library), together with extra code in this executable, to find the hailstone length returned most often for 1 ≤ n < 100,000.
Explain any extra setup/run steps needed to complete the task.
Notes:
It is assumed that for a language that overwhelmingly ships in a compiled form, such as C, the library must also be an executable and the compiled user of that library is to do so without changing the compiled library. I.e. the compile tool-chain is assumed not to be present in the runtime environment.
Interpreters are present in the runtime environment. | #J | J | hailseq=: -:`(1 3&p.)@.(2&|) ^:(1 ~: ]) ^:a:"0
9!:29]1
9!:27'main 0'
main=:3 :0
smoutput 'Hailstone sequence for the number 27'
smoutput hailseq 27
smoutput ''
smoutput 'Finding number with longest hailstone sequence which is'
smoutput 'less than 100000 (and finding that sequence length):'
smoutput (I.@(= >./),>./) #@hailseq i.1e5
) |
http://rosettacode.org/wiki/Extreme_floating_point_values | Extreme floating point values | The IEEE floating point specification defines certain 'extreme' floating point values such as minus zero, -0.0, a value distinct from plus zero; not a number, NaN; and plus and minus infinity.
The task is to use expressions involving other 'normal' floating point values in your language to calculate these, (and maybe other), extreme floating point values in your language and assign them to variables.
Print the values of these variables if possible; and show some arithmetic with these values and variables.
If your language can directly enter these extreme floating point values then show it.
See also
What Every Computer Scientist Should Know About Floating-Point Arithmetic
Related tasks
Infinity
Detect division by zero
Literals/Floating point
| #Ruby | Ruby | inf = 1.0 / 0.0 # or Float::INFINITY
nan = 0.0 / 0.0 # or Float::NAN
expression = [
"1.0 / 0.0", "-1.0 / 0.0", "0.0 / 0.0", "- 0.0",
"inf + 1", "5 - inf", "inf * 5", "inf / 5", "inf * 0",
"1.0 / inf", "-1.0 / inf", "inf + inf", "inf - inf",
"inf * inf", "inf / inf", "inf * 0.0", " 0 < inf", "inf == inf",
"nan + 1", "nan * 5", "nan - nan", "nan * inf", "- nan",
"nan == nan", "nan > 0", "nan < 0", "nan == 0", "nan <=> 0.0", "0.0 == -0.0",
]
expression.each do |exp|
puts "%15s => %p" % [exp, eval(exp)]
end |
http://rosettacode.org/wiki/Execute_SNUSP | Execute SNUSP | Execute SNUSP is an implementation of SNUSP.
Other implementations of SNUSP.
RCSNUSP
SNUSP
An implementation need only properly implement the Core SNUSP instructions ('$', '\', '/', '+', '-', '<', '>', ',', '.', '!', and '?'). Modular SNUSP ('#', '@') and Bloated SNUSP (':', ';', '%', and '&') are also allowed, but not required. Any extra characters that you implement should be noted in the description of your implementation. Any cell size is allowed, EOF support is optional, as is whether you have bounded or unbounded memory.
| #Perl | Perl | with javascript_semantics
integer id = 0, ipr = 1, ipc = 1
procedure step()
if and_bits(id,1) == 0 then
ipc += 1 - and_bits(id,2)
else
ipr += 1 - and_bits(id,2)
end if
end procedure
procedure snusp(integer dlen, string s)
sequence ds = repeat(0,dlen) -- data store
integer dp = 1 -- data pointer
-- remove leading '\n' from string if present
s = trim_head(s,'\n')
-- make 2 dimensional instruction store and set instruction pointers
sequence cs = split(s,'\n')
ipr = 1
ipc = 1
-- look for starting instruction
for i=1 to length(cs) do
ipc = find('$',cs[i])
if ipc then
ipr = i
exit
end if
end for
id = 0
-- execute
while ipr>=1 and ipr<=length(cs)
and ipc>=1 and ipc<=length(cs[ipr]) do
integer op = cs[ipr][ipc]
switch op do
case '>' : dp += 1
case '<' : dp -= 1
case '+' : ds[dp] += 1
case '-' : ds[dp] -= 1
case '.' : puts(1,ds[dp])
case ',' : ds[dp] = getc(0)
case '/' : id = not_bits(id)
case '\\': id = xor_bits(id,1)
case '!' : step()
case '?' : if ds[dp]=0 then step() end if
end switch
step()
end while
end procedure
constant hw = """
/++++!/===========?\>++.>+.+++++++..+++\
\+++\ | /+>+++++++>/ /++++++++++<<.++>./
$+++/ | \+++++++++>\ \+++++.>.+++.-----\
\==-<<<<+>+++/ /=.>.+>.--------.-/"""
snusp(5, hw)
|
http://rosettacode.org/wiki/Extend_your_language | Extend your language | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other languages go much further. Most notably in the Forth and Lisp families, programming per se is done by extending the language without any formal distinction between built-in and user-defined elements.
If your language supports it, show how to introduce a new flow control mechanism. A practical and useful example is a four-way branch:
Occasionally, code must be written that depends on two conditions, resulting in up to four branches (depending on whether both, only the first, only the second, or none of the conditions are "true"). In a C-like language this could look like the following:
if (condition1isTrue) {
if (condition2isTrue)
bothConditionsAreTrue();
else
firstConditionIsTrue();
}
else if (condition2isTrue)
secondConditionIsTrue();
else
noConditionIsTrue();
Besides being rather cluttered, the statement(s) for 'condition2isTrue' must be written down twice. If 'condition2isTrue' were a lengthy and involved expression, it would be quite unreadable, and the code generated by the compiler might be unnecessarily large.
This can be improved by introducing a new keyword if2. It is similar to if, but takes two conditional statements instead of one, and up to three 'else' statements. One proposal (in pseudo-C syntax) might be:
if2 (condition1isTrue) (condition2isTrue)
bothConditionsAreTrue();
else1
firstConditionIsTrue();
else2
secondConditionIsTrue();
else
noConditionIsTrue();
Pick the syntax which suits your language. The keywords 'else1' and 'else2' are just examples. The new conditional expression should look, nest and behave analogously to the language's built-in 'if' statement.
| #Haskell | Haskell | if2 :: Bool -> Bool -> a -> a -> a -> a -> a
if2 p1 p2 e12 e1 e2 e =
if p1 then
if p2 then e12 else e1
else if p2 then e2 else e
main = print $ if2 True False (error "TT") "TF" (error "FT") (error "FF")
|
http://rosettacode.org/wiki/Exponentiation_order | Exponentiation order | This task will demonstrate the order of exponentiation (xy) when there are multiple exponents.
(Many programming languages, especially those with extended─precision integer arithmetic, usually support one of **, ^, ↑ or some such for exponentiation.)
Task requirements
Show the result of a language's evaluation of multiple exponentiation (either as an integer or floating point).
If your language's exponentiation operator is not one of the usual ones, please comment on how to recognize it.
Using whatever operator or syntax your language supports (if any), show the results in three lines (with identification):
5**3**2
(5**3)**2
5**(3**2)
If there are other methods (or formats) of multiple exponentiations, show them as well.
See also
MathWorld entry: exponentiation
Related tasks
exponentiation operator
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #Rust | Rust | fn main() {
println!("5**3**2 = {:7}", 5u32.pow(3).pow(2));
println!("(5**3)**2 = {:7}", (5u32.pow(3)).pow(2));
println!("5**(3**2) = {:7}", 5u32.pow(3u32.pow(2)));
} |
http://rosettacode.org/wiki/Exponentiation_order | Exponentiation order | This task will demonstrate the order of exponentiation (xy) when there are multiple exponents.
(Many programming languages, especially those with extended─precision integer arithmetic, usually support one of **, ^, ↑ or some such for exponentiation.)
Task requirements
Show the result of a language's evaluation of multiple exponentiation (either as an integer or floating point).
If your language's exponentiation operator is not one of the usual ones, please comment on how to recognize it.
Using whatever operator or syntax your language supports (if any), show the results in three lines (with identification):
5**3**2
(5**3)**2
5**(3**2)
If there are other methods (or formats) of multiple exponentiations, show them as well.
See also
MathWorld entry: exponentiation
Related tasks
exponentiation operator
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #Scala | Scala | $ include "seed7_05.s7i";
const proc: main is func
begin
writeln("5**3**2 = " <& 5**3**2);
writeln("(5**3)**2 = " <& (5**3)**2);
writeln("5**(3**2) = " <& 5**(3**2));
end func; |
http://rosettacode.org/wiki/Exponentiation_order | Exponentiation order | This task will demonstrate the order of exponentiation (xy) when there are multiple exponents.
(Many programming languages, especially those with extended─precision integer arithmetic, usually support one of **, ^, ↑ or some such for exponentiation.)
Task requirements
Show the result of a language's evaluation of multiple exponentiation (either as an integer or floating point).
If your language's exponentiation operator is not one of the usual ones, please comment on how to recognize it.
Using whatever operator or syntax your language supports (if any), show the results in three lines (with identification):
5**3**2
(5**3)**2
5**(3**2)
If there are other methods (or formats) of multiple exponentiations, show them as well.
See also
MathWorld entry: exponentiation
Related tasks
exponentiation operator
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #Seed7 | Seed7 | $ include "seed7_05.s7i";
const proc: main is func
begin
writeln("5**3**2 = " <& 5**3**2);
writeln("(5**3)**2 = " <& (5**3)**2);
writeln("5**(3**2) = " <& 5**(3**2));
end func; |
http://rosettacode.org/wiki/Exponentiation_order | Exponentiation order | This task will demonstrate the order of exponentiation (xy) when there are multiple exponents.
(Many programming languages, especially those with extended─precision integer arithmetic, usually support one of **, ^, ↑ or some such for exponentiation.)
Task requirements
Show the result of a language's evaluation of multiple exponentiation (either as an integer or floating point).
If your language's exponentiation operator is not one of the usual ones, please comment on how to recognize it.
Using whatever operator or syntax your language supports (if any), show the results in three lines (with identification):
5**3**2
(5**3)**2
5**(3**2)
If there are other methods (or formats) of multiple exponentiations, show them as well.
See also
MathWorld entry: exponentiation
Related tasks
exponentiation operator
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #Sidef | Sidef | var a = [
'5**3**2',
'(5**3)**2',
'5**(3**2)',
'5 ** 3 ** 2',
'5 ** 3**2',
'5**3 ** 2',
'[5,3,2]«**»',
]
a.each {|e|
"%-12s == %s\n".printf(e, eval(e))
} |
http://rosettacode.org/wiki/Filter | Filter | Task
Select certain elements from an Array into a new Array in a generic way.
To demonstrate, select all even numbers from an Array.
As an option, give a second solution which filters destructively,
by modifying the original Array rather than creating a new Array.
| #ZX_Spectrum_Basic | ZX Spectrum Basic | 10 LET items=100: LET filtered=0
20 DIM a(items)
30 FOR i=1 TO items
40 LET a(i)=INT (RND*items)
50 NEXT i
60 FOR i=1 TO items
70 IF FN m(a(i),2)=0 THEN LET filtered=filtered+1: LET a(filtered)=a(i)
80 NEXT i
90 DIM b(filtered)
100 FOR i=1 TO filtered
110 LET b(i)=a(i): PRINT b(i);" ";
120 NEXT i
130 DIM a(1): REM To free memory (well, almost all)
140 DEF FN m(a,b)=a-INT (a/b)*b |
http://rosettacode.org/wiki/FizzBuzz | FizzBuzz | Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuzz (instead of the number)
The FizzBuzz problem was presented as the lowest level of comprehension required to illustrate adequacy.
Also see
(a blog) dont-overthink-fizzbuzz
(a blog) fizzbuzz-the-programmers-stairway-to-heaven
| #RapidQ | RapidQ | FOR i=1 TO 100
t$ = IIF(i MOD 3 = 0, "Fizz", "") + IIF(i MOD 5 = 0, "Buzz", "")
PRINT IIF(LEN(t$), t$, i)
NEXT i |
http://rosettacode.org/wiki/Extensible_prime_generator | Extensible prime generator | Task
Write a generator of prime numbers, in order, that will automatically adjust to accommodate the generation of any reasonably high prime.
The routine should demonstrably rely on either:
Being based on an open-ended counter set to count without upper limit other than system or programming language limits. In this case, explain where this counter is in the code.
Being based on a limit that is extended automatically. In this case, choose a small limit that ensures the limit will be passed when generating some of the values to be asked for below.
If other methods of creating an extensible prime generator are used, the algorithm's means of extensibility/lack of limits should be stated.
The routine should be used to:
Show the first twenty primes.
Show the primes between 100 and 150.
Show the number of primes between 7,700 and 8,000.
Show the 10,000th prime.
Show output on this page.
Note: You may reference code already on this site if it is written to be imported/included, then only the code necessary for import and the performance of this task need be shown. (It is also important to leave a forward link on the referenced tasks entry so that later editors know that the code is used for multiple tasks).
Note 2: If a languages in-built prime generator is extensible or is guaranteed to generate primes up to a system limit, (231 or memory overflow for example), then this may be used as long as an explanation of the limits of the prime generator is also given. (Which may include a link to/excerpt from, language documentation).
Note 3:The task is written so it may be useful in solving the task Emirp primes as well as others (depending on its efficiency).
Reference
Prime Numbers. Website with large count of primes.
| #J | J | p:i.20
2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71
(#~ >:&100)i.&.(p:inv) 150
101 103 107 109 113 127 131 137 139 149
#(#~ >:&7700)i.&.(p:inv) 8000
30
p:10000-1
104729 |
http://rosettacode.org/wiki/Fibonacci_sequence | Fibonacci sequence | The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are generally considered too slow and are mostly used as an exercise in recursion).
The sequence is sometimes extended into negative numbers by using a straightforward inverse of the positive definition:
Fn = Fn+2 - Fn+1, if n<0
support for negative n in the solution is optional.
Related tasks
Fibonacci n-step number sequences
Leonardo numbers
References
Wikipedia, Fibonacci number
Wikipedia, Lucas number
MathWorld, Fibonacci Number
Some identities for r-Fibonacci numbers
OEIS Fibonacci numbers
OEIS Lucas numbers
| #Hope | Hope | dec f : num -> num;
--- f 0 <= 0;
--- f 1 <= 1;
--- f(n+2) <= f n + f(n+1); |
http://rosettacode.org/wiki/Factors_of_an_integer | Factors of an integer |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |
Comparison |
Matching
Memory Operations
Pointers & references |
Addresses
Task
Compute the factors of a positive integer.
These factors are the positive integers by which the number being factored can be divided to yield a positive integer result.
(Though the concepts function correctly for zero and negative integers, the set of factors of zero has countably infinite members, and the factors of negative integers can be obtained from the factors of related positive numbers without difficulty; this task does not require handling of either of these cases).
Note that every prime number has two factors: 1 and itself.
Related tasks
count in factors
prime decomposition
Sieve of Eratosthenes
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
sequence: smallest number greater than previous term with exactly n divisors
| #REALbasic | REALbasic | Function factors(num As UInt64) As UInt64()
'This function accepts an unsigned 64 bit integer as input and returns an array of unsigned 64 bit integers
Dim result() As UInt64
Dim iFactor As UInt64 = 1
While iFactor <= num/2 'Since a factor will never be larger than half of the number
If num Mod iFactor = 0 Then
result.Append(iFactor)
End If
iFactor = iFactor + 1
Wend
result.Append(num) 'Since a given number is always a factor of itself
Return result
End Function |
http://rosettacode.org/wiki/Execute_HQ9%2B | Execute HQ9+ | Task
Implement a HQ9+ interpreter or compiler.
| #D | D | import std.stdio, std.string;
void main(in string[] args) {
if (args.length != 2 ||
args[1].length != args[1].countchars("hHqQ9+")) {
writeln("Not valid HQ9+ code.");
return;
}
ulong accumulator;
foreach (immutable c; args[1]) {
final switch(c) {
case 'Q', 'q':
writeln(args[1]);
break;
case 'H', 'h':
writeln("Hello, world!");
break;
case '9':
int bottles = 99;
while (bottles > 1) {
writeln(bottles, " bottles of beer on the wall,");
writeln(bottles, " bottles of beer.");
writeln("Take one down, pass it around,");
if (--bottles > 1)
writeln(bottles,
" bottles of beer on the wall.\n");
}
writeln("1 bottle of beer on the wall.\n");
break;
case '+':
accumulator++;
break;
}
}
} |
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call | Exceptions/Catch an exception thrown in a nested call | Show how to create a user-defined exception and show how to catch an exception raised from several nested calls away.
Create two user-defined exceptions, U0 and U1.
Have function foo call function bar twice.
Have function bar call function baz.
Arrange for function baz to raise, or throw exception U0 on its first call, then exception U1 on its second.
Function foo should catch only exception U0, not U1.
Show/describe what happens when the program is run.
| #APL | APL | :Namespace Traps
⍝ Traps (exceptions) are just numbers
⍝ 500-999 are reserved for the user
U0 U1←900 901
⍝ Catch
∇foo;i
:For i :In ⍳2
:Trap U0
bar i
:Else
⎕←'foo caught U0'
:EndTrap
:EndFor
∇
⍝ Throw
∇bar i
⎕SIGNAL U0 U1[i]
∇
:EndNamespace |
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call | Exceptions/Catch an exception thrown in a nested call | Show how to create a user-defined exception and show how to catch an exception raised from several nested calls away.
Create two user-defined exceptions, U0 and U1.
Have function foo call function bar twice.
Have function bar call function baz.
Arrange for function baz to raise, or throw exception U0 on its first call, then exception U1 on its second.
Function foo should catch only exception U0, not U1.
Show/describe what happens when the program is run.
| #AutoHotkey | AutoHotkey | global U0 := Exception("First Exception")
global U1 := Exception("Second Exception")
foo()
foo(){
try
bar()
catch e
MsgBox % "An exception was raised: " e.Message
bar()
}
bar(){
baz()
}
baz(){
static calls := 0
if ( ++calls = 1 )
throw U0
else if ( calls = 2 )
throw U1
} |
http://rosettacode.org/wiki/Exceptions | Exceptions | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
This task is to give an example of an exception handling routine
and to "throw" a new exception.
Related task
Exceptions Through Nested Calls
| #11l | 11l | T SillyError
String message
F (message)
.message = message
X.try
X SillyError(‘egg’)
X.catch SillyError se
print(se.message) |
http://rosettacode.org/wiki/Execute_a_system_command | Execute a system command | Task
Run either the ls system command (dir on Windows), or the pause system command.
Related task
Get system command output
| #Ada | Ada | with POSIX.Unsafe_Process_Primitives;
procedure Execute_A_System_Command is
Arguments : POSIX.POSIX_String_List;
begin
POSIX.Append (Arguments, "ls");
POSIX.Unsafe_Process_Primitives.Exec_Search ("ls", Arguments);
end Execute_A_System_Command; |
http://rosettacode.org/wiki/Execute_a_system_command | Execute a system command | Task
Run either the ls system command (dir on Windows), or the pause system command.
Related task
Get system command output
| #Aikido | Aikido |
var lines = system ("ls")
foreach line lines {
println (line)
}
|
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterative or recursive.
Support for trapping negative n errors is optional.
Related task
Primorial numbers
| #ABAP | ABAP | form factorial using iv_val type i.
data: lv_res type i value 1.
do iv_val times.
multiply lv_res by sy-index.
enddo.
iv_val = lv_res.
endform. |
http://rosettacode.org/wiki/Exponentiation_operator | Exponentiation operator | Most programming languages have a built-in implementation of exponentiation.
Task
Re-implement integer exponentiation for both intint and floatint as both a procedure, and an operator (if your language supports operator definition).
If the language supports operator (or procedure) overloading, then an overloaded form should be provided for both intint and floatint variants.
Related tasks
Exponentiation order
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #Common_Lisp | Common Lisp | (defun my-expt-do (a b)
(do ((x 1 (* x a))
(y 0 (+ y 1)))
((= y b) x))) |
http://rosettacode.org/wiki/Exponentiation_operator | Exponentiation operator | Most programming languages have a built-in implementation of exponentiation.
Task
Re-implement integer exponentiation for both intint and floatint as both a procedure, and an operator (if your language supports operator definition).
If the language supports operator (or procedure) overloading, then an overloaded form should be provided for both intint and floatint variants.
Related tasks
Exponentiation order
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #D | D | import std.stdio, std.conv;
struct Number(T) {
T x; // base
alias x this;
string toString() const { return text(x); }
Number opBinary(string op)(in int exponent)
const pure nothrow @nogc if (op == "^^") in {
if (exponent < 0)
assert (x != 0, "Division by zero");
} body {
debug puts("opBinary ^^");
int zerodir;
T factor;
if (exponent < 0) {
zerodir = +1;
factor = T(1) / x;
} else {
zerodir = -1;
factor = x;
}
T result = 1;
int e = exponent;
while (e != 0)
if (e % 2 != 0) {
result *= factor;
e += zerodir;
} else {
factor *= factor;
e /= 2;
}
return Number(result);
}
}
void main() {
alias Double = Number!double;
writeln(Double(2.5) ^^ 5);
alias Int = Number!int;
writeln(Int(3) ^^ 3);
writeln(Int(0) ^^ -2); // Division by zero.
} |
http://rosettacode.org/wiki/Executable_library | Executable library | The general idea behind an executable library is to create a library
that when used as a library does one thing;
but has the ability to be run directly via command line.
Thus the API comes with a CLI in the very same source code file.
Task detail
Create a library/module/dll/shared object/... for a programming language that contains a function/method called hailstone that is a function taking a positive integer and returns the Hailstone sequence for that number.
The library, when executed directly should satisfy the remaining requirements of the Hailstone sequence task:
2. Use the routine to show that the hailstone sequence for the number 27 has 112 elements starting with 27, 82, 41, 124 and ending with 8, 4, 2, 1
3. Show the number less than 100,000 which has the longest hailstone sequence together with that sequence's length.
Create a second executable to calculate the following:
Use the library's hailstone function, in the standard manner, (or document how this use deviates from standard use of a library), together with extra code in this executable, to find the hailstone length returned most often for 1 ≤ n < 100,000.
Explain any extra setup/run steps needed to complete the task.
Notes:
It is assumed that for a language that overwhelmingly ships in a compiled form, such as C, the library must also be an executable and the compiled user of that library is to do so without changing the compiled library. I.e. the compile tool-chain is assumed not to be present in the runtime environment.
Interpreters are present in the runtime environment. | #Java | Java |
import java.util.ArrayList;
import java.util.List;
// task 1
public class HailstoneSequence {
public static void main(String[] args) {
// task 2
int n = 27;
List<Long> sequence27 = hailstoneSequence(n);
System.out.printf("Hailstone sequence for %d has a length of %d:%nhailstone(%d) = %s%n", n, sequence27.size(), n, sequence27);
// task 3
int maxN = 0;
int maxLength = 0;
for ( int i = 1 ; i < 100_000 ; i++ ) {
int seqLength = hailstoneSequence(i).size();
if ( seqLength > maxLength ) {
maxLength = seqLength;
maxN = i;
}
}
System.out.printf("Longest hailstone sequence less than 100,000: hailstone(%d).length() = %d", maxN, maxLength);
}
public static List<Long> hailstoneSequence(long n) {
if ( n <= 0 ) {
throw new IllegalArgumentException("Must be grater than or equal to zero.");
}
List<Long> sequence = new ArrayList<>();
sequence.add(n);
while ( n > 1 ) {
if ( (n & 1) == 0 ) {
n /= 2;
}
else {
n = 3 * n + 1;
}
sequence.add(n);
}
return sequence;
}
}
|
http://rosettacode.org/wiki/Extreme_floating_point_values | Extreme floating point values | The IEEE floating point specification defines certain 'extreme' floating point values such as minus zero, -0.0, a value distinct from plus zero; not a number, NaN; and plus and minus infinity.
The task is to use expressions involving other 'normal' floating point values in your language to calculate these, (and maybe other), extreme floating point values in your language and assign them to variables.
Print the values of these variables if possible; and show some arithmetic with these values and variables.
If your language can directly enter these extreme floating point values then show it.
See also
What Every Computer Scientist Should Know About Floating-Point Arithmetic
Related tasks
Infinity
Detect division by zero
Literals/Floating point
| #Rust | Rust | fn main() {
let inf: f64 = 1. / 0.; // or std::f64::INFINITY
let minus_inf: f64 = -1. / 0.; // or std::f64::NEG_INFINITY
let minus_zero: f64 = -1. / inf; // or -0.0
let nan: f64 = 0. / 0.; // or std::f64::NAN
// or std::f32 for the above
println!("positive infinity: {:+}", inf);
println!("negative infinity: {:+}", minus_inf);
println!("negative zero: {:+?}", minus_zero);
println!("not a number: {:+}", nan);
println!();
println!("+inf + 2.0 = {:+}", inf + 2.);
println!("+inf - 10.0 = {:+}", inf - 10.);
println!("+inf + -inf = {:+}", inf + minus_inf);
println!("0.0 * inf = {:+}", 0. * inf);
println!("1.0 / -0.0 = {:+}", 1. / -0.);
println!("NaN + 1.0 = {:+}", nan + 1.);
println!("NaN + NaN = {:+}", nan + nan);
println!();
println!("NaN == NaN = {}", nan == nan);
println!("0.0 == -0.0 = {}", 0. == -0.);
} |
http://rosettacode.org/wiki/Extreme_floating_point_values | Extreme floating point values | The IEEE floating point specification defines certain 'extreme' floating point values such as minus zero, -0.0, a value distinct from plus zero; not a number, NaN; and plus and minus infinity.
The task is to use expressions involving other 'normal' floating point values in your language to calculate these, (and maybe other), extreme floating point values in your language and assign them to variables.
Print the values of these variables if possible; and show some arithmetic with these values and variables.
If your language can directly enter these extreme floating point values then show it.
See also
What Every Computer Scientist Should Know About Floating-Point Arithmetic
Related tasks
Infinity
Detect division by zero
Literals/Floating point
| #S-lang | S-lang | foreach $1 ([{-0.0}, {_Inf, "1.0/0"}, {-_Inf, "-1.0/0"}, {_NaN}]) {
() = printf("%S", $1[0]);
if (length($1) > 1) () = printf("\t%S\n", eval($1[1]));
else () = printf("\n");
} |
http://rosettacode.org/wiki/Execute_SNUSP | Execute SNUSP | Execute SNUSP is an implementation of SNUSP.
Other implementations of SNUSP.
RCSNUSP
SNUSP
An implementation need only properly implement the Core SNUSP instructions ('$', '\', '/', '+', '-', '<', '>', ',', '.', '!', and '?'). Modular SNUSP ('#', '@') and Bloated SNUSP (':', ';', '%', and '&') are also allowed, but not required. Any extra characters that you implement should be noted in the description of your implementation. Any cell size is allowed, EOF support is optional, as is whether you have bounded or unbounded memory.
| #Phix | Phix | with javascript_semantics
integer id = 0, ipr = 1, ipc = 1
procedure step()
if and_bits(id,1) == 0 then
ipc += 1 - and_bits(id,2)
else
ipr += 1 - and_bits(id,2)
end if
end procedure
procedure snusp(integer dlen, string s)
sequence ds = repeat(0,dlen) -- data store
integer dp = 1 -- data pointer
-- remove leading '\n' from string if present
s = trim_head(s,'\n')
-- make 2 dimensional instruction store and set instruction pointers
sequence cs = split(s,'\n')
ipr = 1
ipc = 1
-- look for starting instruction
for i=1 to length(cs) do
ipc = find('$',cs[i])
if ipc then
ipr = i
exit
end if
end for
id = 0
-- execute
while ipr>=1 and ipr<=length(cs)
and ipc>=1 and ipc<=length(cs[ipr]) do
integer op = cs[ipr][ipc]
switch op do
case '>' : dp += 1
case '<' : dp -= 1
case '+' : ds[dp] += 1
case '-' : ds[dp] -= 1
case '.' : puts(1,ds[dp])
case ',' : ds[dp] = getc(0)
case '/' : id = not_bits(id)
case '\\': id = xor_bits(id,1)
case '!' : step()
case '?' : if ds[dp]=0 then step() end if
end switch
step()
end while
end procedure
constant hw = """
/++++!/===========?\>++.>+.+++++++..+++\
\+++\ | /+>+++++++>/ /++++++++++<<.++>./
$+++/ | \+++++++++>\ \+++++.>.+++.-----\
\==-<<<<+>+++/ /=.>.+>.--------.-/"""
snusp(5, hw)
|
http://rosettacode.org/wiki/Extend_your_language | Extend your language | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other languages go much further. Most notably in the Forth and Lisp families, programming per se is done by extending the language without any formal distinction between built-in and user-defined elements.
If your language supports it, show how to introduce a new flow control mechanism. A practical and useful example is a four-way branch:
Occasionally, code must be written that depends on two conditions, resulting in up to four branches (depending on whether both, only the first, only the second, or none of the conditions are "true"). In a C-like language this could look like the following:
if (condition1isTrue) {
if (condition2isTrue)
bothConditionsAreTrue();
else
firstConditionIsTrue();
}
else if (condition2isTrue)
secondConditionIsTrue();
else
noConditionIsTrue();
Besides being rather cluttered, the statement(s) for 'condition2isTrue' must be written down twice. If 'condition2isTrue' were a lengthy and involved expression, it would be quite unreadable, and the code generated by the compiler might be unnecessarily large.
This can be improved by introducing a new keyword if2. It is similar to if, but takes two conditional statements instead of one, and up to three 'else' statements. One proposal (in pseudo-C syntax) might be:
if2 (condition1isTrue) (condition2isTrue)
bothConditionsAreTrue();
else1
firstConditionIsTrue();
else2
secondConditionIsTrue();
else
noConditionIsTrue();
Pick the syntax which suits your language. The keywords 'else1' and 'else2' are just examples. The new conditional expression should look, nest and behave analogously to the language's built-in 'if' statement.
| #Icon_and_Unicon | Icon and Unicon | procedure main(A)
if2 { (A[1] = A[2]), (A[3] = A[4]), # Use PDCO with all three else clauses
write("1: both true"),
write("1: only first true"),
write("1: only second true"),
write("1: neither true")
}
if2 { (A[1] = A[2]), (A[3] = A[4]), # Use same PDCO with only one else clause
write("2: both true"),
write("2: only first true"),
}
end
procedure if2(A) # The double-conditional PDCO
suspend if @A[1] then
if @A[2] then |@A[3] # Run-err if missing 'then' clause
else @\A[4] # (all else clauses are optional)
else if @A[2] then |@\A[5]
else |@\A[6]
end |
http://rosettacode.org/wiki/Exponentiation_order | Exponentiation order | This task will demonstrate the order of exponentiation (xy) when there are multiple exponents.
(Many programming languages, especially those with extended─precision integer arithmetic, usually support one of **, ^, ↑ or some such for exponentiation.)
Task requirements
Show the result of a language's evaluation of multiple exponentiation (either as an integer or floating point).
If your language's exponentiation operator is not one of the usual ones, please comment on how to recognize it.
Using whatever operator or syntax your language supports (if any), show the results in three lines (with identification):
5**3**2
(5**3)**2
5**(3**2)
If there are other methods (or formats) of multiple exponentiations, show them as well.
See also
MathWorld entry: exponentiation
Related tasks
exponentiation operator
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #Simula | Simula | OutText("5** 3 **2: "); OutInt(5** 3 **2, 0); Outimage;
OutText("(5**3)**2: "); OutInt((5**3)**2, 0); Outimage;
OutText("5**(3**2): "); OutInt(5**(3**2), 0); Outimage |
http://rosettacode.org/wiki/Exponentiation_order | Exponentiation order | This task will demonstrate the order of exponentiation (xy) when there are multiple exponents.
(Many programming languages, especially those with extended─precision integer arithmetic, usually support one of **, ^, ↑ or some such for exponentiation.)
Task requirements
Show the result of a language's evaluation of multiple exponentiation (either as an integer or floating point).
If your language's exponentiation operator is not one of the usual ones, please comment on how to recognize it.
Using whatever operator or syntax your language supports (if any), show the results in three lines (with identification):
5**3**2
(5**3)**2
5**(3**2)
If there are other methods (or formats) of multiple exponentiations, show them as well.
See also
MathWorld entry: exponentiation
Related tasks
exponentiation operator
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #Smalltalk | Smalltalk | Transcript show:'5**3**2 => '; showCR: 5**3**2.
Transcript show:'(5**3)**2 => '; showCR: (5**3)**2.
Transcript show:'5**(3**2) => '; showCR: 5**(3**2). |
http://rosettacode.org/wiki/Exponentiation_order | Exponentiation order | This task will demonstrate the order of exponentiation (xy) when there are multiple exponents.
(Many programming languages, especially those with extended─precision integer arithmetic, usually support one of **, ^, ↑ or some such for exponentiation.)
Task requirements
Show the result of a language's evaluation of multiple exponentiation (either as an integer or floating point).
If your language's exponentiation operator is not one of the usual ones, please comment on how to recognize it.
Using whatever operator or syntax your language supports (if any), show the results in three lines (with identification):
5**3**2
(5**3)**2
5**(3**2)
If there are other methods (or formats) of multiple exponentiations, show them as well.
See also
MathWorld entry: exponentiation
Related tasks
exponentiation operator
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #Stata | Stata | . di (5^3^2)
15625
. di ((5^3)^2)
15625
. di (5^(3^2))
1953125 |
http://rosettacode.org/wiki/Exponentiation_order | Exponentiation order | This task will demonstrate the order of exponentiation (xy) when there are multiple exponents.
(Many programming languages, especially those with extended─precision integer arithmetic, usually support one of **, ^, ↑ or some such for exponentiation.)
Task requirements
Show the result of a language's evaluation of multiple exponentiation (either as an integer or floating point).
If your language's exponentiation operator is not one of the usual ones, please comment on how to recognize it.
Using whatever operator or syntax your language supports (if any), show the results in three lines (with identification):
5**3**2
(5**3)**2
5**(3**2)
If there are other methods (or formats) of multiple exponentiations, show them as well.
See also
MathWorld entry: exponentiation
Related tasks
exponentiation operator
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #Swift | Swift | precedencegroup ExponentiationPrecedence {
associativity: left
higherThan: MultiplicationPrecedence
}
infix operator ** : ExponentiationPrecedence
@inlinable
public func ** <T: BinaryInteger>(lhs: T, rhs: T) -> T {
guard lhs != 0 else {
return 1
}
var x = lhs
var n = rhs
var y = T(1)
while n > 1 {
switch n & 1 {
case 0:
n /= 2
case 1:
y *= x
n = (n - 1) / 2
case _:
fatalError()
}
x *= x
}
return x * y
}
print(5 ** 3 ** 2)
print((5 ** 3) ** 2)
print(5 ** (3 ** 2)) |
http://rosettacode.org/wiki/FizzBuzz | FizzBuzz | Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuzz (instead of the number)
The FizzBuzz problem was presented as the lowest level of comprehension required to illustrate adequacy.
Also see
(a blog) dont-overthink-fizzbuzz
(a blog) fizzbuzz-the-programmers-stairway-to-heaven
| #Rascal | Rascal | import IO;
public void fizzbuzz() {
for(int n <- [1 .. 100]){
fb = ((n % 3 == 0) ? "Fizz" : "") + ((n % 5 == 0) ? "Buzz" : "");
println((fb == "") ?"<n>" : fb);
}
} |
http://rosettacode.org/wiki/Extensible_prime_generator | Extensible prime generator | Task
Write a generator of prime numbers, in order, that will automatically adjust to accommodate the generation of any reasonably high prime.
The routine should demonstrably rely on either:
Being based on an open-ended counter set to count without upper limit other than system or programming language limits. In this case, explain where this counter is in the code.
Being based on a limit that is extended automatically. In this case, choose a small limit that ensures the limit will be passed when generating some of the values to be asked for below.
If other methods of creating an extensible prime generator are used, the algorithm's means of extensibility/lack of limits should be stated.
The routine should be used to:
Show the first twenty primes.
Show the primes between 100 and 150.
Show the number of primes between 7,700 and 8,000.
Show the 10,000th prime.
Show output on this page.
Note: You may reference code already on this site if it is written to be imported/included, then only the code necessary for import and the performance of this task need be shown. (It is also important to leave a forward link on the referenced tasks entry so that later editors know that the code is used for multiple tasks).
Note 2: If a languages in-built prime generator is extensible or is guaranteed to generate primes up to a system limit, (231 or memory overflow for example), then this may be used as long as an explanation of the limits of the prime generator is also given. (Which may include a link to/excerpt from, language documentation).
Note 3:The task is written so it may be useful in solving the task Emirp primes as well as others (depending on its efficiency).
Reference
Prime Numbers. Website with large count of primes.
| #Java | Java | import java.util.*;
public class PrimeGenerator {
private int limit_;
private int index_ = 0;
private int increment_;
private int count_ = 0;
private List<Integer> primes_ = new ArrayList<>();
private BitSet sieve_ = new BitSet();
private int sieveLimit_ = 0;
public PrimeGenerator(int initialLimit, int increment) {
limit_ = nextOddNumber(initialLimit);
increment_ = increment;
primes_.add(2);
findPrimes(3);
}
public int nextPrime() {
if (index_ == primes_.size()) {
if (Integer.MAX_VALUE - increment_ < limit_)
return 0;
int start = limit_ + 2;
limit_ = nextOddNumber(limit_ + increment_);
primes_.clear();
findPrimes(start);
}
++count_;
return primes_.get(index_++);
}
public int count() {
return count_;
}
private void findPrimes(int start) {
index_ = 0;
int newLimit = sqrt(limit_);
for (int p = 3; p * p <= newLimit; p += 2) {
if (sieve_.get(p/2 - 1))
continue;
int q = p * Math.max(p, nextOddNumber((sieveLimit_ + p - 1)/p));
for (; q <= newLimit; q += 2*p)
sieve_.set(q/2 - 1, true);
}
sieveLimit_ = newLimit;
int count = (limit_ - start)/2 + 1;
BitSet composite = new BitSet(count);
for (int p = 3; p <= newLimit; p += 2) {
if (sieve_.get(p/2 - 1))
continue;
int q = p * Math.max(p, nextOddNumber((start + p - 1)/p)) - start;
q /= 2;
for (; q >= 0 && q < count; q += p)
composite.set(q, true);
}
for (int p = 0; p < count; ++p) {
if (!composite.get(p))
primes_.add(p * 2 + start);
}
}
private static int sqrt(int n) {
return nextOddNumber((int)Math.sqrt(n));
}
private static int nextOddNumber(int n) {
return 1 + 2 * (n/2);
}
public static void main(String[] args) {
PrimeGenerator pgen = new PrimeGenerator(20, 200000);
System.out.println("First 20 primes:");
for (int i = 0; i < 20; ++i) {
if (i > 0)
System.out.print(", ");
System.out.print(pgen.nextPrime());
}
System.out.println();
System.out.println("Primes between 100 and 150:");
for (int i = 0; ; ) {
int prime = pgen.nextPrime();
if (prime > 150)
break;
if (prime >= 100) {
if (i++ != 0)
System.out.print(", ");
System.out.print(prime);
}
}
System.out.println();
int count = 0;
for (;;) {
int prime = pgen.nextPrime();
if (prime > 8000)
break;
if (prime >= 7700)
++count;
}
System.out.println("Number of primes between 7700 and 8000: " + count);
int n = 10000;
for (;;) {
int prime = pgen.nextPrime();
if (prime == 0) {
System.out.println("Can't generate any more primes.");
break;
}
if (pgen.count() == n) {
System.out.println(n + "th prime: " + prime);
n *= 10;
}
}
}
} |
http://rosettacode.org/wiki/Fibonacci_sequence | Fibonacci sequence | The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are generally considered too slow and are mostly used as an exercise in recursion).
The sequence is sometimes extended into negative numbers by using a straightforward inverse of the positive definition:
Fn = Fn+2 - Fn+1, if n<0
support for negative n in the solution is optional.
Related tasks
Fibonacci n-step number sequences
Leonardo numbers
References
Wikipedia, Fibonacci number
Wikipedia, Lucas number
MathWorld, Fibonacci Number
Some identities for r-Fibonacci numbers
OEIS Fibonacci numbers
OEIS Lucas numbers
| #Hy | Hy | (defn fib [n]
(if (< n 2)
n
(+ (fib (- n 2)) (fib (- n 1))))) |
http://rosettacode.org/wiki/Factors_of_an_integer | Factors of an integer |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |
Comparison |
Matching
Memory Operations
Pointers & references |
Addresses
Task
Compute the factors of a positive integer.
These factors are the positive integers by which the number being factored can be divided to yield a positive integer result.
(Though the concepts function correctly for zero and negative integers, the set of factors of zero has countably infinite members, and the factors of negative integers can be obtained from the factors of related positive numbers without difficulty; this task does not require handling of either of these cases).
Note that every prime number has two factors: 1 and itself.
Related tasks
count in factors
prime decomposition
Sieve of Eratosthenes
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
sequence: smallest number greater than previous term with exactly n divisors
| #Red | Red | Red []
factors: function [n [integer!]] [
n: absolute n
collect [
repeat i (sq: sqrt n) - 1 [
if n % i = 0 [
keep i
keep n / i
]
]
if sq = sq: to-integer sq [keep sq]
]
]
foreach num [
24
-64 ; negative
64 ; square
101 ; prime
123456789 ; large
][
print mold/flat sort factors num
] |
http://rosettacode.org/wiki/Factors_of_an_integer | Factors of an integer |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |
Comparison |
Matching
Memory Operations
Pointers & references |
Addresses
Task
Compute the factors of a positive integer.
These factors are the positive integers by which the number being factored can be divided to yield a positive integer result.
(Though the concepts function correctly for zero and negative integers, the set of factors of zero has countably infinite members, and the factors of negative integers can be obtained from the factors of related positive numbers without difficulty; this task does not require handling of either of these cases).
Note that every prime number has two factors: 1 and itself.
Related tasks
count in factors
prime decomposition
Sieve of Eratosthenes
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
sequence: smallest number greater than previous term with exactly n divisors
| #Relation | Relation |
program factors(num)
relation fact
insert 1
set i = 2
while i < num / 2
if num / i = floor(num/i)
insert i
end if
set i = i + 1
end while
insert num
print
end program
|
http://rosettacode.org/wiki/Execute_HQ9%2B | Execute HQ9+ | Task
Implement a HQ9+ interpreter or compiler.
| #Delphi | Delphi |
uses
System.SysUtils;
procedure runCode(code: string);
var
c_len, i, bottles: Integer;
accumulator: Cardinal;
begin
c_len := Length(code);
accumulator := 0;
for i := 1 to c_len do
begin
case code[i] of
'Q':
writeln(code);
'H':
Writeln('Hello, world!');
'9':
begin
bottles := 99;
repeat
writeln(format('%d bottles of beer on the wall', [bottles]));
writeln(format('%d bottles of beer', [bottles]));
Writeln('Take one down, pass it around');
dec(bottles);
writeln(format('%d bottles of beer on the wall' + sLineBreak, [bottles]));
until (bottles <= 0);
end;
'+':
inc(accumulator);
end;
end;
end; |
http://rosettacode.org/wiki/Execute_a_Markov_algorithm | Execute a Markov algorithm | Execute a Markov algorithm
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create an interpreter for a Markov Algorithm.
Rules have the syntax:
<ruleset> ::= ((<comment> | <rule>) <newline>+)*
<comment> ::= # {<any character>}
<rule> ::= <pattern> <whitespace> -> <whitespace> [.] <replacement>
<whitespace> ::= (<tab> | <space>) [<whitespace>]
There is one rule per line.
If there is a . (period) present before the <replacement>, then this is a terminating rule in which case the interpreter must halt execution.
A ruleset consists of a sequence of rules, with optional comments.
Rulesets
Use the following tests on entries:
Ruleset 1
# This rules file is extracted from Wikipedia:
# http://en.wikipedia.org/wiki/Markov_Algorithm
A -> apple
B -> bag
S -> shop
T -> the
the shop -> my brother
a never used -> .terminating rule
Sample text of:
I bought a B of As from T S.
Should generate the output:
I bought a bag of apples from my brother.
Ruleset 2
A test of the terminating rule
# Slightly modified from the rules on Wikipedia
A -> apple
B -> bag
S -> .shop
T -> the
the shop -> my brother
a never used -> .terminating rule
Sample text of:
I bought a B of As from T S.
Should generate:
I bought a bag of apples from T shop.
Ruleset 3
This tests for correct substitution order and may trap simple regexp based replacement routines if special regexp characters are not escaped.
# BNF Syntax testing rules
A -> apple
WWWW -> with
Bgage -> ->.*
B -> bag
->.* -> money
W -> WW
S -> .shop
T -> the
the shop -> my brother
a never used -> .terminating rule
Sample text of:
I bought a B of As W my Bgage from T S.
Should generate:
I bought a bag of apples with my money from T shop.
Ruleset 4
This tests for correct order of scanning of rules, and may trap replacement routines that scan in the wrong order. It implements a general unary multiplication engine. (Note that the input expression must be placed within underscores in this implementation.)
### Unary Multiplication Engine, for testing Markov Algorithm implementations
### By Donal Fellows.
# Unary addition engine
_+1 -> _1+
1+1 -> 11+
# Pass for converting from the splitting of multiplication into ordinary
# addition
1! -> !1
,! -> !+
_! -> _
# Unary multiplication by duplicating left side, right side times
1*1 -> x,@y
1x -> xX
X, -> 1,1
X1 -> 1X
_x -> _X
,x -> ,X
y1 -> 1y
y_ -> _
# Next phase of applying
1@1 -> x,@y
1@_ -> @_
,@_ -> !_
++ -> +
# Termination cleanup for addition
_1 -> 1
1+_ -> 1
_+_ ->
Sample text of:
_1111*11111_
should generate the output:
11111111111111111111
Ruleset 5
A simple Turing machine,
implementing a three-state busy beaver.
The tape consists of 0s and 1s, the states are A, B, C and H (for Halt), and the head position is indicated by writing the state letter before the character where the head is.
All parts of the initial tape the machine operates on have to be given in the input.
Besides demonstrating that the Markov algorithm is Turing-complete, it also made me catch a bug in the C++ implementation which wasn't caught by the first four rulesets.
# Turing machine: three-state busy beaver
#
# state A, symbol 0 => write 1, move right, new state B
A0 -> 1B
# state A, symbol 1 => write 1, move left, new state C
0A1 -> C01
1A1 -> C11
# state B, symbol 0 => write 1, move left, new state A
0B0 -> A01
1B0 -> A11
# state B, symbol 1 => write 1, move right, new state B
B1 -> 1B
# state C, symbol 0 => write 1, move left, new state B
0C0 -> B01
1C0 -> B11
# state C, symbol 1 => write 1, move left, halt
0C1 -> H01
1C1 -> H11
This ruleset should turn
000000A000000
into
00011H1111000
| #11l | 11l | T Rule
String pattern
String replacement
Bool terminating
F (pattern, replacement, terminating)
.pattern = pattern
.replacement = replacement
.terminating = terminating
F parse(rules)
[Rule] result
L(line) rules.split("\n")
I line.starts_with(‘#’)
L.continue
I line.trim(‘ ’).empty
L.continue
V (pat, rep) = line.split(‘ -> ’)
V terminating = 0B
I rep.starts_with(‘.’)
rep = rep[1..]
terminating = 1B
result.append(Rule(pat, rep, terminating))
R result
F apply(text, rules)
V result = text
V changed = 1B
L changed == 1B
changed = 0B
L(rule) rules
I rule.pattern C result
result = result.replace(rule.pattern, rule.replacement)
I rule.terminating
R result
changed = 1B
L.break
R result
V SampleTexts = [‘I bought a B of As from T S.’,
‘I bought a B of As from T S.’,
‘I bought a B of As W my Bgage from T S.’,
‘_1111*11111_’,
‘000000A000000’]
V RuleSets = [
‘# This rules file is extracted from Wikipedia:
# http://en.wikipedia.org/wiki/Markov_Algorithm
A -> apple
B -> bag
S -> shop
T -> the
the shop -> my brother
a never used -> .terminating rule’,
‘# Slightly modified from the rules on Wikipedia
A -> apple
B -> bag
S -> .shop
T -> the
the shop -> my brother
a never used -> .terminating rule’,
‘# BNF Syntax testing rules
A -> apple
WWWW -> with
Bgage -> ->.*
B -> bag
->.* -> money
W -> WW
S -> .shop
T -> the
the shop -> my brother
a never used -> .terminating rule’,
‘### Unary Multiplication Engine, for testing Markov Algorithm implementations
### By Donal Fellows.
# Unary addition engine
_+1 -> _1+
1+1 -> 11+
# Pass for converting from the splitting of multiplication into ordinary
# addition
1! -> !1
,! -> !+
_! -> _
# Unary multiplication by duplicating left side, right side times
1*1 -> x,@y
1x -> xX
X, -> 1,1
X1 -> 1X
_x -> _X
,x -> ,X
y1 -> 1y
y_ -> _
# Next phase of applying
1@1 -> x,@y
1@_ -> @_
,@_ -> !_
++ -> +
# Termination cleanup for addition
_1 -> 1
1+_ -> 1
_+_ -> ’,
‘# Turing machine: three-state busy beaver
#
# state A, symbol 0 => write 1, move right, new state B
A0 -> 1B
# state A, symbol 1 => write 1, move left, new state C
0A1 -> C01
1A1 -> C11
# state B, symbol 0 => write 1, move left, new state A
0B0 -> A01
1B0 -> A11
# state B, symbol 1 => write 1, move right, new state B
B1 -> 1B
# state C, symbol 0 => write 1, move left, new state B
0C0 -> B01
1C0 -> B11
# state C, symbol 1 => write 1, move left, halt
0C1 -> H01
1C1 -> H11’]
L(ruleset) RuleSets
V rules = parse(ruleset)
print(apply(SampleTexts[L.index], rules)) |
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call | Exceptions/Catch an exception thrown in a nested call | Show how to create a user-defined exception and show how to catch an exception raised from several nested calls away.
Create two user-defined exceptions, U0 and U1.
Have function foo call function bar twice.
Have function bar call function baz.
Arrange for function baz to raise, or throw exception U0 on its first call, then exception U1 on its second.
Function foo should catch only exception U0, not U1.
Show/describe what happens when the program is run.
| #BBC_BASIC | BBC BASIC | REM Allocate error numbers:
U0& = 123
U1& = 124
PROCfoo
END
DEF PROCfoo
ON ERROR LOCAL IF ERR = U0& THEN PRINT "Exception U0 caught in foo" ELSE \
\ RESTORE ERROR : ERROR ERR, REPORT$
PROCbar
PROCbar
ENDPROC
DEF PROCbar
PROCbaz
ENDPROC
DEF PROCbaz
PRIVATE called%
called% += 1
CASE called% OF
WHEN 1: ERROR U0&, "Exception U0 thrown"
WHEN 2: ERROR U1&, "Exception U1 thrown"
ENDCASE
ENDPROC
|
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call | Exceptions/Catch an exception thrown in a nested call | Show how to create a user-defined exception and show how to catch an exception raised from several nested calls away.
Create two user-defined exceptions, U0 and U1.
Have function foo call function bar twice.
Have function bar call function baz.
Arrange for function baz to raise, or throw exception U0 on its first call, then exception U1 on its second.
Function foo should catch only exception U0, not U1.
Show/describe what happens when the program is run.
| #C | C | #include <stdio.h>
#include <stdlib.h>
typedef struct exception {
int extype;
char what[128];
} exception;
typedef struct exception_ctx {
exception * exs;
int size;
int pos;
} exception_ctx;
exception_ctx * Create_Ex_Ctx(int length) {
const int safety = 8; // alignment precaution.
char * tmp = (char*) malloc(safety+sizeof(exception_ctx)+sizeof(exception)*length);
if (! tmp) return NULL;
exception_ctx * ctx = (exception_ctx*)tmp;
ctx->size = length;
ctx->pos = -1;
ctx->exs = (exception*) (tmp + sizeof(exception_ctx));
return ctx;
}
void Free_Ex_Ctx(exception_ctx * ctx) {
free(ctx);
}
int Has_Ex(exception_ctx * ctx) {
return (ctx->pos >= 0) ? 1 : 0;
}
int Is_Ex_Type(exception_ctx * exctx, int extype) {
return (exctx->pos >= 0 && exctx->exs[exctx->pos].extype == extype) ? 1 : 0;
}
void Pop_Ex(exception_ctx * ctx) {
if (ctx->pos >= 0) --ctx->pos;
}
const char * Get_What(exception_ctx * ctx) {
if (ctx->pos >= 0) return ctx->exs[ctx->pos].what;
return NULL;
}
int Push_Ex(exception_ctx * exctx, int extype, const char * msg) {
if (++exctx->pos == exctx->size) {
// Use last slot and report error.
--exctx->pos;
fprintf(stderr, "*** Error: Overflow in exception context.\n");
}
snprintf(exctx->exs[exctx->pos].what, sizeof(exctx->exs[0].what), "%s", msg);
exctx->exs[exctx->pos].extype = extype;
return -1;
}
//////////////////////////////////////////////////////////////////////
exception_ctx * GLOBALEX = NULL;
enum { U0_DRINK_ERROR = 10, U1_ANGRYBARTENDER_ERROR };
void baz(int n) {
if (! n) {
Push_Ex(GLOBALEX, U0_DRINK_ERROR , "U0 Drink Error. Insufficient drinks in bar Baz.");
return;
}
else {
Push_Ex(GLOBALEX, U1_ANGRYBARTENDER_ERROR , "U1 Bartender Error. Bartender kicked customer out of bar Baz.");
return;
}
}
void bar(int n) {
fprintf(stdout, "Bar door is open.\n");
baz(n);
if (Has_Ex(GLOBALEX)) goto bar_cleanup;
fprintf(stdout, "Baz has been called without errors.\n");
bar_cleanup:
fprintf(stdout, "Bar door is closed.\n");
}
void foo() {
fprintf(stdout, "Foo entering bar.\n");
bar(0);
while (Is_Ex_Type(GLOBALEX, U0_DRINK_ERROR)) {
fprintf(stderr, "I am foo() and I deaall wrth U0 DriNk Errors with my own bottle... GOT oNE! [%s]\n", Get_What(GLOBALEX));
Pop_Ex(GLOBALEX);
}
if (Has_Ex(GLOBALEX)) return;
fprintf(stdout, "Foo left the bar.\n");
fprintf(stdout, "Foo entering bar again.\n");
bar(1);
while (Is_Ex_Type(GLOBALEX, U0_DRINK_ERROR)) {
fprintf(stderr, "I am foo() and I deaall wrth U0 DriNk Errors with my own bottle... GOT oNE! [%s]\n", Get_What(GLOBALEX));
Pop_Ex(GLOBALEX);
}
if (Has_Ex(GLOBALEX)) return;
fprintf(stdout, "Foo left the bar.\n");
}
int main(int argc, char ** argv) {
exception_ctx * ctx = Create_Ex_Ctx(5);
GLOBALEX = ctx;
foo();
if (Has_Ex(ctx)) goto main_ex;
fprintf(stdout, "No errors encountered.\n");
main_ex:
while (Has_Ex(ctx)) {
fprintf(stderr, "*** Error: %s\n", Get_What(ctx));
Pop_Ex(ctx);
}
Free_Ex_Ctx(ctx);
return 0;
}
|
http://rosettacode.org/wiki/Exceptions | Exceptions | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
This task is to give an example of an exception handling routine
and to "throw" a new exception.
Related task
Exceptions Through Nested Calls
| #8086_Assembly | 8086 Assembly | ;syscall for creating a new file.
mov dx,offset filename
mov cx,0
mov ah,5Bh
int 21h
;if error occurs, will return carry set and error code in ax
;Error code 03h = path not found
;Error code 04h = Too many open files
;Error code 05h = Access denied
;Error code 50h = File already exists
jnc noError ;continue with program
cmp ax,03h
je PathNotFoundError ;unimplemented exception handler
cmp ax,04h
je TooManyOpenFilesError
cmp ax,05h
je AccessDeniedError
cmp ax,50h
je FileAlreadyExistsError
noError: |
http://rosettacode.org/wiki/Exceptions | Exceptions | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
This task is to give an example of an exception handling routine
and to "throw" a new exception.
Related task
Exceptions Through Nested Calls
| #Ada | Ada | Foo_Error : exception; |
http://rosettacode.org/wiki/Execute_a_system_command | Execute a system command | Task
Run either the ls system command (dir on Windows), or the pause system command.
Related task
Get system command output
| #Aime | Aime | sshell ss;
ss.argv.insert("ls");
o_(ss.link);
|
http://rosettacode.org/wiki/Execute_a_system_command | Execute a system command | Task
Run either the ls system command (dir on Windows), or the pause system command.
Related task
Get system command output
| #ALGOL_68 | ALGOL 68 | system("ls") |
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterative or recursive.
Support for trapping negative n errors is optional.
Related task
Primorial numbers
| #Action.21 | Action! | CARD FUNC Factorial(INT n BYTE POINTER err)
CARD i,res
IF n<0 THEN
err^=1 RETURN (0)
ELSEIF n>8 THEN
err^=2 RETURN (0)
FI
res=1
FOR i=2 TO n
DO
res=res*i
OD
err^=0
RETURN (res)
PROC Main()
INT i,f
BYTE err
FOR i=-2 TO 10
DO
f=Factorial(i,@err)
IF err=0 THEN
PrintF("%I!=%U%E",i,f)
ELSEIF err=1 THEN
PrintF("%I is negative value%E",i)
ELSE
PrintF("%I! is to big%E",i)
FI
OD
RETURN |
http://rosettacode.org/wiki/Exponentiation_operator | Exponentiation operator | Most programming languages have a built-in implementation of exponentiation.
Task
Re-implement integer exponentiation for both intint and floatint as both a procedure, and an operator (if your language supports operator definition).
If the language supports operator (or procedure) overloading, then an overloaded form should be provided for both intint and floatint variants.
Related tasks
Exponentiation order
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #Delphi | Delphi |
program Exponentiation_operator;
{$APPTYPE CONSOLE}
uses
System.SysUtils;
type
TDouble = record
Value: Double;
class operator Implicit(a: TDouble): Double;
class operator Implicit(a: Double): TDouble;
class operator Implicit(a: TDouble): string;
class operator LogicalXor(a: TDouble; b: Integer): TDouble;
end;
TInteger = record
Value: Integer;
class operator Implicit(a: TInteger): Integer;
class operator Implicit(a: Integer): TInteger;
class operator Implicit(a: TInteger): string;
class operator LogicalXor(a: TInteger; b: Integer): TInteger;
end;
{ TDouble }
class operator TDouble.Implicit(a: TDouble): Double;
begin
Result := a.Value;
end;
class operator TDouble.Implicit(a: Double): TDouble;
begin
Result.Value := a;
end;
class operator TDouble.Implicit(a: TDouble): string;
begin
Result := a.Value.ToString;
end;
class operator TDouble.LogicalXor(a: TDouble; b: Integer): TDouble;
var
i: Integer;
val: Double;
begin
val := 1;
for i := 1 to b do
val := val * a.Value;
Result.Value := val;
end;
{ TInteger }
class operator TInteger.Implicit(a: TInteger): Integer;
begin
Result := a.Value;
end;
class operator TInteger.Implicit(a: Integer): TInteger;
begin
Result.Value := a;
end;
class operator TInteger.Implicit(a: TInteger): string;
begin
Result := a.Value.ToString;
end;
class operator TInteger.LogicalXor(a: TInteger; b: Integer): TInteger;
var
val, i: Integer;
begin
if b < 0 then
raise Exception.Create('Expoent must be greater or equal zero');
val := 1;
for i := 1 to b do
val := val * a.Value;
Result.Value := val;
end;
procedure Print(s: string);
begin
Write(s);
end;
var
valF: TDouble;
valI: TInteger;
begin
valF := 5.5;
valI := 5;
// Delphi don't have "**" or "^" operator for overload,
// "xor" operator has used instead
Print('5^5 = ');
Print(valI xor 5);
print(#10);
Print('5.5^5 = ');
Print(valF xor 5);
print(#10);
readln;
end. |
http://rosettacode.org/wiki/Executable_library | Executable library | The general idea behind an executable library is to create a library
that when used as a library does one thing;
but has the ability to be run directly via command line.
Thus the API comes with a CLI in the very same source code file.
Task detail
Create a library/module/dll/shared object/... for a programming language that contains a function/method called hailstone that is a function taking a positive integer and returns the Hailstone sequence for that number.
The library, when executed directly should satisfy the remaining requirements of the Hailstone sequence task:
2. Use the routine to show that the hailstone sequence for the number 27 has 112 elements starting with 27, 82, 41, 124 and ending with 8, 4, 2, 1
3. Show the number less than 100,000 which has the longest hailstone sequence together with that sequence's length.
Create a second executable to calculate the following:
Use the library's hailstone function, in the standard manner, (or document how this use deviates from standard use of a library), together with extra code in this executable, to find the hailstone length returned most often for 1 ≤ n < 100,000.
Explain any extra setup/run steps needed to complete the task.
Notes:
It is assumed that for a language that overwhelmingly ships in a compiled form, such as C, the library must also be an executable and the compiled user of that library is to do so without changing the compiled library. I.e. the compile tool-chain is assumed not to be present in the runtime environment.
Interpreters are present in the runtime environment. | #Julia | Julia |
############### in file hailstone.jl ###############
module Hailstone
function hailstone(n)
ret = [n]
while n > 1
if n & 1 > 0
n = 3n + 1
else
n = Int(n//2)
end
append!(ret, n)
end
return ret
end
export hailstone
end
if PROGRAM_FILE == "hailstone.jl"
using Hailstone
h = hailstone(27)
n = length(h)
println("The sequence of hailstone(27) is:\n $h.\nThis sequence is of length $n. It starts with $(h[1:4]) and ends with $(h[n-3:end]).")
end
############ in file moduletest.jl ####################
include("hailstone.jl")
using Hailstone
function countstones(mi, mx)
lengths2occurences = Dict()
mostfreq = mi
maxcount = 1
for i in mi:mx
h = hailstone(i)
n = length(h)
if haskey(lengths2occurences, n)
newoccurences = lengths2occurences[n] + 1
if newoccurences > maxcount
maxcount = newoccurences
mostfreq = n
end
lengths2occurences[n] = newoccurences
else
lengths2occurences[n] = 1
end
end
mostfreq, maxcount
end
nlen, cnt = countstones(1,99999)
print("The most common hailstone sequence length for hailstone(n) for 1 <= n < 100000 is $nlen, which occurs $cnt times.")
|
http://rosettacode.org/wiki/Executable_library | Executable library | The general idea behind an executable library is to create a library
that when used as a library does one thing;
but has the ability to be run directly via command line.
Thus the API comes with a CLI in the very same source code file.
Task detail
Create a library/module/dll/shared object/... for a programming language that contains a function/method called hailstone that is a function taking a positive integer and returns the Hailstone sequence for that number.
The library, when executed directly should satisfy the remaining requirements of the Hailstone sequence task:
2. Use the routine to show that the hailstone sequence for the number 27 has 112 elements starting with 27, 82, 41, 124 and ending with 8, 4, 2, 1
3. Show the number less than 100,000 which has the longest hailstone sequence together with that sequence's length.
Create a second executable to calculate the following:
Use the library's hailstone function, in the standard manner, (or document how this use deviates from standard use of a library), together with extra code in this executable, to find the hailstone length returned most often for 1 ≤ n < 100,000.
Explain any extra setup/run steps needed to complete the task.
Notes:
It is assumed that for a language that overwhelmingly ships in a compiled form, such as C, the library must also be an executable and the compiled user of that library is to do so without changing the compiled library. I.e. the compile tool-chain is assumed not to be present in the runtime environment.
Interpreters are present in the runtime environment. | #Limbo | Limbo | implement Execlib;
include "sys.m"; sys: Sys;
include "draw.m";
Execlib: module {
init: fn(ctxt: ref Draw->Context, args: list of string);
hailstone: fn(i: big): list of big;
};
init(nil: ref Draw->Context, nil: list of string)
{
sys = load Sys Sys->PATH;
seq := hailstone(big 27);
l := len seq;
sys->print("hailstone(27): ");
for(i := 0; i < 4; i++) {
sys->print("%bd, ", hd seq);
seq = tl seq;
}
sys->print("⋯");
while(len seq > 4)
seq = tl seq;
while(seq != nil) {
sys->print(", %bd", hd seq);
seq = tl seq;
}
sys->print(" (length %d)\n", l);
max := 1;
maxn := big 1;
for(n := big 2; n < big 100000; n++) {
cur := len hailstone(n);
if(cur > max) {
max = cur;
maxn = n;
}
}
sys->print("hailstone(%bd) has length %d\n", maxn, max);
}
hailstone(i: big): list of big
{
if(i == big 1)
return big 1 :: nil;
if(i % big 2 == big 0)
return i :: hailstone(i / big 2);
return i :: hailstone(big 3 * i + big 1);
}
|
http://rosettacode.org/wiki/Executable_library | Executable library | The general idea behind an executable library is to create a library
that when used as a library does one thing;
but has the ability to be run directly via command line.
Thus the API comes with a CLI in the very same source code file.
Task detail
Create a library/module/dll/shared object/... for a programming language that contains a function/method called hailstone that is a function taking a positive integer and returns the Hailstone sequence for that number.
The library, when executed directly should satisfy the remaining requirements of the Hailstone sequence task:
2. Use the routine to show that the hailstone sequence for the number 27 has 112 elements starting with 27, 82, 41, 124 and ending with 8, 4, 2, 1
3. Show the number less than 100,000 which has the longest hailstone sequence together with that sequence's length.
Create a second executable to calculate the following:
Use the library's hailstone function, in the standard manner, (or document how this use deviates from standard use of a library), together with extra code in this executable, to find the hailstone length returned most often for 1 ≤ n < 100,000.
Explain any extra setup/run steps needed to complete the task.
Notes:
It is assumed that for a language that overwhelmingly ships in a compiled form, such as C, the library must also be an executable and the compiled user of that library is to do so without changing the compiled library. I.e. the compile tool-chain is assumed not to be present in the runtime environment.
Interpreters are present in the runtime environment. | #Lua | Lua | #!/usr/bin/env luajit
bit32=bit32 or bit
local lib={
hailstone=function(n)
local seq={n}
while n>1 do
n=bit32.band(n,1)==1 and 3*n+1 or n/2
seq[#seq+1]=n
end
return seq
end
}
if arg[0] and arg[0]:match("hailstone.lua") then
local function printf(fmt, ...) io.write(string.format(fmt, ...)) end
local seq=lib.hailstone(27)
printf("27 has %d numbers in sequence:\n",#seq)
for _,i in ipairs(seq) do
printf("%d ", i)
end
printf("\n")
else
return lib
end
|
http://rosettacode.org/wiki/Extreme_floating_point_values | Extreme floating point values | The IEEE floating point specification defines certain 'extreme' floating point values such as minus zero, -0.0, a value distinct from plus zero; not a number, NaN; and plus and minus infinity.
The task is to use expressions involving other 'normal' floating point values in your language to calculate these, (and maybe other), extreme floating point values in your language and assign them to variables.
Print the values of these variables if possible; and show some arithmetic with these values and variables.
If your language can directly enter these extreme floating point values then show it.
See also
What Every Computer Scientist Should Know About Floating-Point Arithmetic
Related tasks
Infinity
Detect division by zero
Literals/Floating point
| #Scala | Scala | object ExtremeFloatingPoint extends App {
val negInf = -1.0 / 0.0 //also Double.NegativeInfinity
val inf = 1.0 / 0.0 // //also Double.PositiveInfinity
val nan = 0.0 / 0.0 // //also Double.NaN
val negZero = -2.0 / inf
println("Value: Result: Infinity? Whole?")
println(f"Negative inf: ${negInf}%9s ${negInf.isInfinity}%9s ${negInf.isWhole}%9s")
println(f"Positive inf: ${inf}%9s ${inf.isInfinity}%9s ${inf.isWhole}%9s")
println(f"NaN: ${nan}%9s ${nan.isInfinity}%9s ${nan.isWhole}%9s")
println(f"Negative 0: ${negZero}%9s ${negZero.isInfinity}%9s ${negZero.isWhole}%9s")
println(f"inf + -inf: ${inf + negInf}%9s ${(inf + negInf).isInfinity}%9s ${(inf + negInf).isWhole}%9s")
println(f"0 * NaN: ${0 * nan}%9s ${(inf + negInf).isInfinity}%9s ${(inf + negInf).isWhole}%9s")
println(f"NaN == NaN: ${nan == nan}%9s")
} |
http://rosettacode.org/wiki/Extreme_floating_point_values | Extreme floating point values | The IEEE floating point specification defines certain 'extreme' floating point values such as minus zero, -0.0, a value distinct from plus zero; not a number, NaN; and plus and minus infinity.
The task is to use expressions involving other 'normal' floating point values in your language to calculate these, (and maybe other), extreme floating point values in your language and assign them to variables.
Print the values of these variables if possible; and show some arithmetic with these values and variables.
If your language can directly enter these extreme floating point values then show it.
See also
What Every Computer Scientist Should Know About Floating-Point Arithmetic
Related tasks
Infinity
Detect division by zero
Literals/Floating point
| #Scheme | Scheme | (define infinity (/ 1.0 0.0))
(define minus-infinity (- infinity))
(define zero 0.0)
(define minus-zero (- zero))
(define not-a-number (/ 0.0 0.0))
(equal? (list infinity minus-infinity zero minus-zero not-a-number)
(list +inf.0 -inf.0 0.0 -0.0 +nan.0))
; #t
|
http://rosettacode.org/wiki/Execute_SNUSP | Execute SNUSP | Execute SNUSP is an implementation of SNUSP.
Other implementations of SNUSP.
RCSNUSP
SNUSP
An implementation need only properly implement the Core SNUSP instructions ('$', '\', '/', '+', '-', '<', '>', ',', '.', '!', and '?'). Modular SNUSP ('#', '@') and Bloated SNUSP (':', ';', '%', and '&') are also allowed, but not required. Any extra characters that you implement should be noted in the description of your implementation. Any cell size is allowed, EOF support is optional, as is whether you have bounded or unbounded memory.
| #PicoLisp | PicoLisp | #!/usr/bin/env python3
HW = r'''
/++++!/===========?\>++.>+.+++++++..+++\
\+++\ | /+>+++++++>/ /++++++++++<<.++>./
$+++/ | \+++++++++>\ \+++++.>.+++.-----\
\==-<<<<+>+++/ /=.>.+>.--------.-/'''
def snusp(store, code):
ds = bytearray(store) # data store
dp = 0 # data pointer
cs = code.splitlines() # 2 dimensional code store
ipr, ipc = 0, 0 # instruction pointers in row and column
for r, row in enumerate(cs):
try:
ipc = row.index('$')
ipr = r
break
except ValueError:
pass
rt, dn, lt, up = range(4)
id = rt # instruction direction. starting direction is always rt
def step():
nonlocal ipr, ipc
if id&1:
ipr += 1 - (id&2)
else:
ipc += 1 - (id&2)
while ipr >= 0 and ipr < len(cs) and ipc >= 0 and ipc < len(cs[ipr]):
op = cs[ipr][ipc]
if op == '>':
dp += 1
elif op == '<':
dp -= 1
elif op == '+':
ds[dp] += 1
elif op == '-':
ds[dp] -= 1
elif op == '.':
print(chr(ds[dp]), end='')
elif op == ',':
ds[dp] = input()
elif op == '/':
id = ~id
elif op == '\\':
id ^= 1
elif op == '!':
step()
elif op == '?':
if not ds[dp]:
step()
step()
if __name__ == '__main__':
snusp(5, HW) |
http://rosettacode.org/wiki/Execute_SNUSP | Execute SNUSP | Execute SNUSP is an implementation of SNUSP.
Other implementations of SNUSP.
RCSNUSP
SNUSP
An implementation need only properly implement the Core SNUSP instructions ('$', '\', '/', '+', '-', '<', '>', ',', '.', '!', and '?'). Modular SNUSP ('#', '@') and Bloated SNUSP (':', ';', '%', and '&') are also allowed, but not required. Any extra characters that you implement should be noted in the description of your implementation. Any cell size is allowed, EOF support is optional, as is whether you have bounded or unbounded memory.
| #Python | Python | #!/usr/bin/env python3
HW = r'''
/++++!/===========?\>++.>+.+++++++..+++\
\+++\ | /+>+++++++>/ /++++++++++<<.++>./
$+++/ | \+++++++++>\ \+++++.>.+++.-----\
\==-<<<<+>+++/ /=.>.+>.--------.-/'''
def snusp(store, code):
ds = bytearray(store) # data store
dp = 0 # data pointer
cs = code.splitlines() # 2 dimensional code store
ipr, ipc = 0, 0 # instruction pointers in row and column
for r, row in enumerate(cs):
try:
ipc = row.index('$')
ipr = r
break
except ValueError:
pass
rt, dn, lt, up = range(4)
id = rt # instruction direction. starting direction is always rt
def step():
nonlocal ipr, ipc
if id&1:
ipr += 1 - (id&2)
else:
ipc += 1 - (id&2)
while ipr >= 0 and ipr < len(cs) and ipc >= 0 and ipc < len(cs[ipr]):
op = cs[ipr][ipc]
if op == '>':
dp += 1
elif op == '<':
dp -= 1
elif op == '+':
ds[dp] += 1
elif op == '-':
ds[dp] -= 1
elif op == '.':
print(chr(ds[dp]), end='')
elif op == ',':
ds[dp] = input()
elif op == '/':
id = ~id
elif op == '\\':
id ^= 1
elif op == '!':
step()
elif op == '?':
if not ds[dp]:
step()
step()
if __name__ == '__main__':
snusp(5, HW) |
http://rosettacode.org/wiki/Extend_your_language | Extend your language | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other languages go much further. Most notably in the Forth and Lisp families, programming per se is done by extending the language without any formal distinction between built-in and user-defined elements.
If your language supports it, show how to introduce a new flow control mechanism. A practical and useful example is a four-way branch:
Occasionally, code must be written that depends on two conditions, resulting in up to four branches (depending on whether both, only the first, only the second, or none of the conditions are "true"). In a C-like language this could look like the following:
if (condition1isTrue) {
if (condition2isTrue)
bothConditionsAreTrue();
else
firstConditionIsTrue();
}
else if (condition2isTrue)
secondConditionIsTrue();
else
noConditionIsTrue();
Besides being rather cluttered, the statement(s) for 'condition2isTrue' must be written down twice. If 'condition2isTrue' were a lengthy and involved expression, it would be quite unreadable, and the code generated by the compiler might be unnecessarily large.
This can be improved by introducing a new keyword if2. It is similar to if, but takes two conditional statements instead of one, and up to three 'else' statements. One proposal (in pseudo-C syntax) might be:
if2 (condition1isTrue) (condition2isTrue)
bothConditionsAreTrue();
else1
firstConditionIsTrue();
else2
secondConditionIsTrue();
else
noConditionIsTrue();
Pick the syntax which suits your language. The keywords 'else1' and 'else2' are just examples. The new conditional expression should look, nest and behave analogously to the language's built-in 'if' statement.
| #Idris | Idris | if2 : Bool -> Bool -> Lazy a -> Lazy a -> Lazy a -> Lazy a -> a
if2 True True v _ _ _ = v
if2 True False _ v _ _ = v
if2 False True _ _ v _ = v
if2 _ _ _ _ _ v = v |
http://rosettacode.org/wiki/Extend_your_language | Extend your language | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other languages go much further. Most notably in the Forth and Lisp families, programming per se is done by extending the language without any formal distinction between built-in and user-defined elements.
If your language supports it, show how to introduce a new flow control mechanism. A practical and useful example is a four-way branch:
Occasionally, code must be written that depends on two conditions, resulting in up to four branches (depending on whether both, only the first, only the second, or none of the conditions are "true"). In a C-like language this could look like the following:
if (condition1isTrue) {
if (condition2isTrue)
bothConditionsAreTrue();
else
firstConditionIsTrue();
}
else if (condition2isTrue)
secondConditionIsTrue();
else
noConditionIsTrue();
Besides being rather cluttered, the statement(s) for 'condition2isTrue' must be written down twice. If 'condition2isTrue' were a lengthy and involved expression, it would be quite unreadable, and the code generated by the compiler might be unnecessarily large.
This can be improved by introducing a new keyword if2. It is similar to if, but takes two conditional statements instead of one, and up to three 'else' statements. One proposal (in pseudo-C syntax) might be:
if2 (condition1isTrue) (condition2isTrue)
bothConditionsAreTrue();
else1
firstConditionIsTrue();
else2
secondConditionIsTrue();
else
noConditionIsTrue();
Pick the syntax which suits your language. The keywords 'else1' and 'else2' are just examples. The new conditional expression should look, nest and behave analogously to the language's built-in 'if' statement.
| #Inform_7 | Inform 7 | To if2 (c1 - condition) and-or (c2 - condition) begin -- end: (- switch (({c1})*2 + ({c2})) { 3: do -).
To else1 -- in if2: (- } until (1); 2: do { -).
To else2 -- in if2: (- } until (1); 1: do { -).
To else0 -- in if2: (- } until (1); 0: -). |
http://rosettacode.org/wiki/Exponentiation_order | Exponentiation order | This task will demonstrate the order of exponentiation (xy) when there are multiple exponents.
(Many programming languages, especially those with extended─precision integer arithmetic, usually support one of **, ^, ↑ or some such for exponentiation.)
Task requirements
Show the result of a language's evaluation of multiple exponentiation (either as an integer or floating point).
If your language's exponentiation operator is not one of the usual ones, please comment on how to recognize it.
Using whatever operator or syntax your language supports (if any), show the results in three lines (with identification):
5**3**2
(5**3)**2
5**(3**2)
If there are other methods (or formats) of multiple exponentiations, show them as well.
See also
MathWorld entry: exponentiation
Related tasks
exponentiation operator
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #Tcl | Tcl | foreach expression {5**3**2 (5**3)**2 5**(3**2)} {
puts "${expression}:\t[expr $expression]"
} |
http://rosettacode.org/wiki/Exponentiation_order | Exponentiation order | This task will demonstrate the order of exponentiation (xy) when there are multiple exponents.
(Many programming languages, especially those with extended─precision integer arithmetic, usually support one of **, ^, ↑ or some such for exponentiation.)
Task requirements
Show the result of a language's evaluation of multiple exponentiation (either as an integer or floating point).
If your language's exponentiation operator is not one of the usual ones, please comment on how to recognize it.
Using whatever operator or syntax your language supports (if any), show the results in three lines (with identification):
5**3**2
(5**3)**2
5**(3**2)
If there are other methods (or formats) of multiple exponentiations, show them as well.
See also
MathWorld entry: exponentiation
Related tasks
exponentiation operator
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #VBA | VBA | Public Sub exp()
Debug.Print "5^3^2", 5 ^ 3 ^ 2
Debug.Print "(5^3)^2", (5 ^ 3) ^ 2
Debug.Print "5^(3^2)", 5 ^ (3 ^ 2)
End Sub |
http://rosettacode.org/wiki/Exponentiation_order | Exponentiation order | This task will demonstrate the order of exponentiation (xy) when there are multiple exponents.
(Many programming languages, especially those with extended─precision integer arithmetic, usually support one of **, ^, ↑ or some such for exponentiation.)
Task requirements
Show the result of a language's evaluation of multiple exponentiation (either as an integer or floating point).
If your language's exponentiation operator is not one of the usual ones, please comment on how to recognize it.
Using whatever operator or syntax your language supports (if any), show the results in three lines (with identification):
5**3**2
(5**3)**2
5**(3**2)
If there are other methods (or formats) of multiple exponentiations, show them as well.
See also
MathWorld entry: exponentiation
Related tasks
exponentiation operator
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #VBScript | VBScript |
WScript.StdOut.WriteLine "5^3^2 => " & 5^3^2
WScript.StdOut.WriteLine "(5^3)^2 => " & (5^3)^2
WScript.StdOut.WriteLine "5^(3^2) => " & 5^(3^2)
|
http://rosettacode.org/wiki/Exponentiation_order | Exponentiation order | This task will demonstrate the order of exponentiation (xy) when there are multiple exponents.
(Many programming languages, especially those with extended─precision integer arithmetic, usually support one of **, ^, ↑ or some such for exponentiation.)
Task requirements
Show the result of a language's evaluation of multiple exponentiation (either as an integer or floating point).
If your language's exponentiation operator is not one of the usual ones, please comment on how to recognize it.
Using whatever operator or syntax your language supports (if any), show the results in three lines (with identification):
5**3**2
(5**3)**2
5**(3**2)
If there are other methods (or formats) of multiple exponentiations, show them as well.
See also
MathWorld entry: exponentiation
Related tasks
exponentiation operator
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #Verbexx | Verbexx | // Exponentiation order example:
@SAY "5**3**2 = " ( 5**3**2 );
@SAY "(5**3)**2 = " ( (5**3)**2 );
@SAY "5**(3**2) = " ( 5**(3**2) );
/] Output:
5**3**2 = 1953125
(5**3)**2 = 15625
5**(3**2) = 1953125 |
http://rosettacode.org/wiki/FizzBuzz | FizzBuzz | Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuzz (instead of the number)
The FizzBuzz problem was presented as the lowest level of comprehension required to illustrate adequacy.
Also see
(a blog) dont-overthink-fizzbuzz
(a blog) fizzbuzz-the-programmers-stairway-to-heaven
| #Raven | Raven | 100 each 1 + as n
''
n 3 mod 0 = if 'Fizz' cat
n 5 mod 0 = if 'Buzz' cat
dup empty if drop n
say |
http://rosettacode.org/wiki/Extensible_prime_generator | Extensible prime generator | Task
Write a generator of prime numbers, in order, that will automatically adjust to accommodate the generation of any reasonably high prime.
The routine should demonstrably rely on either:
Being based on an open-ended counter set to count without upper limit other than system or programming language limits. In this case, explain where this counter is in the code.
Being based on a limit that is extended automatically. In this case, choose a small limit that ensures the limit will be passed when generating some of the values to be asked for below.
If other methods of creating an extensible prime generator are used, the algorithm's means of extensibility/lack of limits should be stated.
The routine should be used to:
Show the first twenty primes.
Show the primes between 100 and 150.
Show the number of primes between 7,700 and 8,000.
Show the 10,000th prime.
Show output on this page.
Note: You may reference code already on this site if it is written to be imported/included, then only the code necessary for import and the performance of this task need be shown. (It is also important to leave a forward link on the referenced tasks entry so that later editors know that the code is used for multiple tasks).
Note 2: If a languages in-built prime generator is extensible or is guaranteed to generate primes up to a system limit, (231 or memory overflow for example), then this may be used as long as an explanation of the limits of the prime generator is also given. (Which may include a link to/excerpt from, language documentation).
Note 3:The task is written so it may be useful in solving the task Emirp primes as well as others (depending on its efficiency).
Reference
Prime Numbers. Website with large count of primes.
| #JavaScript | JavaScript | function primeGenerator(num, showPrimes) {
var i,
arr = [];
function isPrime(num) {
// try primes <= 16
if (num <= 16) return (
num == 2 || num == 3 || num == 5 || num == 7 || num == 11 || num == 13
);
// cull multiples of 2, 3, 5 or 7
if (num % 2 == 0 || num % 3 == 0 || num % 5 == 0 || num % 7 == 0)
return false;
// cull square numbers ending in 1, 3, 7 or 9
for (var i = 10; i * i <= num; i += 10) {
if (num % (i + 1) == 0) return false;
if (num % (i + 3) == 0) return false;
if (num % (i + 7) == 0) return false;
if (num % (i + 9) == 0) return false;
}
return true;
}
if (typeof num == "number") {
for (i = 0; arr.length < num; i++) if (isPrime(i)) arr.push(i);
// first x primes
if (showPrimes) return arr;
// xth prime
else return arr.pop();
}
if (Array.isArray(num)) {
for (i = num[0]; i <= num[1]; i++) if (isPrime(i)) arr.push(i);
// primes between x .. y
if (showPrimes) return arr;
// number of primes between x .. y
else return arr.length;
}
// throw a default error if nothing returned yet
// (surrogate for a quite long and detailed try-catch-block anywhere before)
throw("Invalid arguments for primeGenerator()");
} |
http://rosettacode.org/wiki/Fibonacci_sequence | Fibonacci sequence | The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are generally considered too slow and are mostly used as an exercise in recursion).
The sequence is sometimes extended into negative numbers by using a straightforward inverse of the positive definition:
Fn = Fn+2 - Fn+1, if n<0
support for negative n in the solution is optional.
Related tasks
Fibonacci n-step number sequences
Leonardo numbers
References
Wikipedia, Fibonacci number
Wikipedia, Lucas number
MathWorld, Fibonacci Number
Some identities for r-Fibonacci numbers
OEIS Fibonacci numbers
OEIS Lucas numbers
| #Icon_and_Unicon | Icon and Unicon | procedure main(args)
write(fib(integer(!args) | 1000)
end
procedure fib(n)
static fCache
initial {
fCache := table()
fCache[0] := 0
fCache[1] := 1
}
/fCache[n] := fib(n-1) + fib(n-2)
return fCache[n]
end |
http://rosettacode.org/wiki/Factors_of_an_integer | Factors of an integer |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |
Comparison |
Matching
Memory Operations
Pointers & references |
Addresses
Task
Compute the factors of a positive integer.
These factors are the positive integers by which the number being factored can be divided to yield a positive integer result.
(Though the concepts function correctly for zero and negative integers, the set of factors of zero has countably infinite members, and the factors of negative integers can be obtained from the factors of related positive numbers without difficulty; this task does not require handling of either of these cases).
Note that every prime number has two factors: 1 and itself.
Related tasks
count in factors
prime decomposition
Sieve of Eratosthenes
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
sequence: smallest number greater than previous term with exactly n divisors
| #REXX | REXX | /*REXX program displays divisors of any [negative/zero/positive] integer or a range.*/
parse arg LO HI inc . /*obtain the optional args*/
HI= word(HI LO 20, 1); LO= word(LO 1,1); inc= word(inc 1,1) /*define the range options*/
w= length(HI) + 2; numeric digits max(9, w-2); != '∞' /*decimal digits for // */
@.=left('',7); @.1= "{unity}"; @.2= '[prime]'; @.!= " {∞} " /*define some literals. */
say center('n', w) "#divisors" center('divisors', 60) /*display the header. */
say copies('═', w) "═════════" copies('═' , 60) /* " " separator. */
pn= 0 /*count of prime numbers. */
do k=2 until sq.k>=HI; sq.k= k*k /*memoization for squares.*/
end /*k*/
do n=LO to HI by inc; $= divs(n); #= words($) /*get list of divs; # divs*/
if $==! then do; #= !; $= ' (infinite)'; end /*handle case for infinity*/
p= @.#; if n<0 then if n\==-1 then p= @.. /* " " " negative*/
if [email protected] then pn= pn + 1 /*Prime? Then bump counter*/
say center(n, w) center('['#"]", 9) "──► " p ' ' $
end /*n*/ /* [↑] process a range of integers. */
say
say right(pn, 20) ' primes were found.' /*display the number of primes found. */
exit 0 /*stick a fork in it, we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
divs: procedure expose sq.; parse arg x 1 b; a=1 /*set X and B to the 1st argument. */
if x<2 then do; x= abs(x); if x==1 then return 1; if x==0 then return '∞'; b=x
end
odd= x // 2 /* [↓] process EVEN or ODD ints. ___*/
do j=2+odd by 1+odd while sq.j<x /*divide by all the integers up to √ x */
if x//j==0 then do; a=a j; b=x%j b; end /*÷? Add divisors to α and ß lists*/
end /*j*/ /* [↑] % ≡ integer division. ___*/
if sq.j==x then return a j b /*Was X a square? Then insert √ x */
return a b /*return the divisors of both lists. */ |
http://rosettacode.org/wiki/Execute_HQ9%2B | Execute HQ9+ | Task
Implement a HQ9+ interpreter or compiler.
| #DWScript | DWScript | procedure RunCode(code : String);
var
i : Integer;
accum, bottles : Integer;
begin
for i:=1 to Length(code) do begin
case code[i] of
'Q', 'q' : PrintLn(code);
'H', 'h' : PrintLn('Hello, world!');
'9' : begin
bottles:=99;
while bottles>1 do begin
Print(bottles); PrintLn(' bottles of beer on the wall,');
Print(bottles); PrintLn(' bottles of beer.');
PrintLn('Take one down, pass it around,');
Dec(bottles);
if bottles>1 then begin
Print(bottles); PrintLn(' bottles of beer on the wall.'#13#10);
end;
end;
PrintLn('1 bottle of beer on the wall.');
end;
'+' : Inc(accum);
else
PrintLn('Syntax Error');
end;
end;
end; |
http://rosettacode.org/wiki/Execute_HQ9%2B | Execute HQ9+ | Task
Implement a HQ9+ interpreter or compiler.
| #Dyalect | Dyalect | func eval(code) {
var accumulator = 0
var opcodes = (
"h": () => print("Hello, World!"),
"q": () => print(code),
"9": () => {
var quantity = 99
while quantity > 1 {
print("\(quantity) bottles of beer on the wall, \(quantity) bottles of beer.")
print("Take one down and pass it around, \(quantity - 1) bottles of beer.")
quantity -= 1
}
print("1 bottle of beer on the wall, 1 bottle of beer.")
print("Take one down and pass it around, no more bottles of beer on the wall.\n")
print("No more bottles of beer on the wall, no more bottles of beer.")
print("Go to the store and buy some more, 99 bottles of beer on the wall.")
},
"+": () => { accumulator += 1 }
)
for c in code {
opcodes[c.Lower()]()
}
} |
http://rosettacode.org/wiki/Execute_a_Markov_algorithm | Execute a Markov algorithm | Execute a Markov algorithm
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create an interpreter for a Markov Algorithm.
Rules have the syntax:
<ruleset> ::= ((<comment> | <rule>) <newline>+)*
<comment> ::= # {<any character>}
<rule> ::= <pattern> <whitespace> -> <whitespace> [.] <replacement>
<whitespace> ::= (<tab> | <space>) [<whitespace>]
There is one rule per line.
If there is a . (period) present before the <replacement>, then this is a terminating rule in which case the interpreter must halt execution.
A ruleset consists of a sequence of rules, with optional comments.
Rulesets
Use the following tests on entries:
Ruleset 1
# This rules file is extracted from Wikipedia:
# http://en.wikipedia.org/wiki/Markov_Algorithm
A -> apple
B -> bag
S -> shop
T -> the
the shop -> my brother
a never used -> .terminating rule
Sample text of:
I bought a B of As from T S.
Should generate the output:
I bought a bag of apples from my brother.
Ruleset 2
A test of the terminating rule
# Slightly modified from the rules on Wikipedia
A -> apple
B -> bag
S -> .shop
T -> the
the shop -> my brother
a never used -> .terminating rule
Sample text of:
I bought a B of As from T S.
Should generate:
I bought a bag of apples from T shop.
Ruleset 3
This tests for correct substitution order and may trap simple regexp based replacement routines if special regexp characters are not escaped.
# BNF Syntax testing rules
A -> apple
WWWW -> with
Bgage -> ->.*
B -> bag
->.* -> money
W -> WW
S -> .shop
T -> the
the shop -> my brother
a never used -> .terminating rule
Sample text of:
I bought a B of As W my Bgage from T S.
Should generate:
I bought a bag of apples with my money from T shop.
Ruleset 4
This tests for correct order of scanning of rules, and may trap replacement routines that scan in the wrong order. It implements a general unary multiplication engine. (Note that the input expression must be placed within underscores in this implementation.)
### Unary Multiplication Engine, for testing Markov Algorithm implementations
### By Donal Fellows.
# Unary addition engine
_+1 -> _1+
1+1 -> 11+
# Pass for converting from the splitting of multiplication into ordinary
# addition
1! -> !1
,! -> !+
_! -> _
# Unary multiplication by duplicating left side, right side times
1*1 -> x,@y
1x -> xX
X, -> 1,1
X1 -> 1X
_x -> _X
,x -> ,X
y1 -> 1y
y_ -> _
# Next phase of applying
1@1 -> x,@y
1@_ -> @_
,@_ -> !_
++ -> +
# Termination cleanup for addition
_1 -> 1
1+_ -> 1
_+_ ->
Sample text of:
_1111*11111_
should generate the output:
11111111111111111111
Ruleset 5
A simple Turing machine,
implementing a three-state busy beaver.
The tape consists of 0s and 1s, the states are A, B, C and H (for Halt), and the head position is indicated by writing the state letter before the character where the head is.
All parts of the initial tape the machine operates on have to be given in the input.
Besides demonstrating that the Markov algorithm is Turing-complete, it also made me catch a bug in the C++ implementation which wasn't caught by the first four rulesets.
# Turing machine: three-state busy beaver
#
# state A, symbol 0 => write 1, move right, new state B
A0 -> 1B
# state A, symbol 1 => write 1, move left, new state C
0A1 -> C01
1A1 -> C11
# state B, symbol 0 => write 1, move left, new state A
0B0 -> A01
1B0 -> A11
# state B, symbol 1 => write 1, move right, new state B
B1 -> 1B
# state C, symbol 0 => write 1, move left, new state B
0C0 -> B01
1C0 -> B11
# state C, symbol 1 => write 1, move left, halt
0C1 -> H01
1C1 -> H11
This ruleset should turn
000000A000000
into
00011H1111000
| #Ada | Ada | with Ada.Strings.Unbounded;
package Markov is
use Ada.Strings.Unbounded;
type Ruleset (Length : Natural) is private;
type String_Array is array (Positive range <>) of Unbounded_String;
function Parse (S : String_Array) return Ruleset;
function Apply (R : Ruleset; S : String) return String;
private
type Entry_Kind is (Comment, Rule);
type Set_Entry (Kind : Entry_Kind := Rule) is record
case Kind is
when Rule =>
Source : Unbounded_String;
Target : Unbounded_String;
Is_Terminating : Boolean;
when Comment =>
Text : Unbounded_String;
end case;
end record;
subtype Rule_Entry is Set_Entry (Kind => Rule);
type Entry_Array is array (Positive range <>) of Set_Entry;
type Ruleset (Length : Natural) is record
Entries : Entry_Array (1 .. Length);
end record;
end Markov; |
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call | Exceptions/Catch an exception thrown in a nested call | Show how to create a user-defined exception and show how to catch an exception raised from several nested calls away.
Create two user-defined exceptions, U0 and U1.
Have function foo call function bar twice.
Have function bar call function baz.
Arrange for function baz to raise, or throw exception U0 on its first call, then exception U1 on its second.
Function foo should catch only exception U0, not U1.
Show/describe what happens when the program is run.
| #C.23 | C# | using System; //Used for Exception and Console classes
class Exceptions
{
class U0 : Exception { }
class U1 : Exception { }
static int i;
static void foo()
{
for (i = 0; i < 2; i++)
try
{
bar();
}
catch (U0) {
Console.WriteLine("U0 Caught");
}
}
static void bar()
{
baz();
}
static void baz(){
if (i == 0)
throw new U0();
throw new U1();
}
public static void Main()
{
foo();
}
} |
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call | Exceptions/Catch an exception thrown in a nested call | Show how to create a user-defined exception and show how to catch an exception raised from several nested calls away.
Create two user-defined exceptions, U0 and U1.
Have function foo call function bar twice.
Have function bar call function baz.
Arrange for function baz to raise, or throw exception U0 on its first call, then exception U1 on its second.
Function foo should catch only exception U0, not U1.
Show/describe what happens when the program is run.
| #C.2B.2B | C++ | #include <iostream>
class U0 {};
class U1 {};
void baz(int i)
{
if (!i) throw U0();
else throw U1();
}
void bar(int i) { baz(i); }
void foo()
{
for (int i = 0; i < 2; i++)
{
try {
bar(i);
} catch(U0 e) {
std::cout<< "Exception U0 caught\n";
}
}
}
int main() {
foo();
std::cout<< "Should never get here!\n";
return 0;
} |
http://rosettacode.org/wiki/Exceptions | Exceptions | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
This task is to give an example of an exception handling routine
and to "throw" a new exception.
Related task
Exceptions Through Nested Calls
| #Aikido | Aikido |
try {
var lines = readfile ("input.txt")
process (lines)
} catch (e) {
do_somthing(e)
}
|
http://rosettacode.org/wiki/Exceptions | Exceptions | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
This task is to give an example of an exception handling routine
and to "throw" a new exception.
Related task
Exceptions Through Nested Calls
| #Aime | Aime | void
throwing(void)
{
o_text("throwing...\n");
error("now!");
}
void
catching(void)
{
o_text("ready to catch\n");
if (trap(throwing)) {
o_text("caught!\n");
} else {
# nothing was thrown
}
}
integer
main(void)
{
catching();
return 0;
} |
http://rosettacode.org/wiki/Execute_a_system_command | Execute a system command | Task
Run either the ls system command (dir on Windows), or the pause system command.
Related task
Get system command output
| #Amazing_Hopper | Amazing Hopper |
#!/usr/bin/hopper
#include <hopper.h>
main:
/* execute "ls -lstar" with no result return (only displayed) */
{"ls -lstar"},execv
/* this form does not allow composition of the line with variables.
Save result in the variable "s", and then display it */
s=`ls -l | awk '{if($2=="2")print $0;}'`
{"\n",s,"\n"}print
data="2"
{""}tok sep
// the same as above, only I can compose the line:
{"ls -l | awk '{if($2==\"",data,"\")print $0;}'"}join(s),{s}exec,print
{"\n\n"}print
// this does the same as above, with an "execute" macro inside a "let" macro:
t=0,let (t := execute( {"ls -l | awk '{if($2==\""},{data},{"\")print $0;}'"} ))
{t,"\n"}print
{0}return
|
http://rosettacode.org/wiki/Execute_a_system_command | Execute a system command | Task
Run either the ls system command (dir on Windows), or the pause system command.
Related task
Get system command output
| #APL | APL |
h ← ⎕fio['fork_daemon'] '/bin/ls /var'
backups games lib lock mail run tmp
cache gemini local log opt spool
⎕fio['fclose'] h
0
|
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterative or recursive.
Support for trapping negative n errors is optional.
Related task
Primorial numbers
| #ActionScript | ActionScript | public static function factorial(n:int):int
{
if (n < 0)
return 0;
var fact:int = 1;
for (var i:int = 1; i <= n; i++)
fact *= i;
return fact;
} |
http://rosettacode.org/wiki/Exponentiation_operator | Exponentiation operator | Most programming languages have a built-in implementation of exponentiation.
Task
Re-implement integer exponentiation for both intint and floatint as both a procedure, and an operator (if your language supports operator definition).
If the language supports operator (or procedure) overloading, then an overloaded form should be provided for both intint and floatint variants.
Related tasks
Exponentiation order
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #E | E | def power(base, exponent :int) {
var r := base
if (exponent < 0) {
for _ in exponent..0 { r /= base }
} else if (exponent <=> 0) {
return 1
} else {
for _ in 2..exponent { r *= base }
}
return r
} |
http://rosettacode.org/wiki/Exponentiation_operator | Exponentiation operator | Most programming languages have a built-in implementation of exponentiation.
Task
Re-implement integer exponentiation for both intint and floatint as both a procedure, and an operator (if your language supports operator definition).
If the language supports operator (or procedure) overloading, then an overloaded form should be provided for both intint and floatint variants.
Related tasks
Exponentiation order
arbitrary-precision integers (included)
Exponentiation with infix operators in (or operating on) the base
| #EchoLisp | EchoLisp |
;; this exponentiation function handles integer, rational or float x.
;; n is a positive or negative integer.
(define (** x n) (cond
((zero? n) 1)
((< n 0) (/ (** x (- n)))) ;; x**-n = 1 / x**n
((= n 1) x)
((= n 0) 1)
((odd? n) (* x (** x (1- n)))) ;; x**(2p+1) = x * x**2p
(else (let ((m (** x (/ n 2)))) (* m m))))) ;; x**2p = (x**p) * (x**p)
(** 3 0) → 1
(** 3 4) → 81
(** 3 5) → 243
(** 10 10) → 10000000000
(** 1.3 10) → 13.785849184900007
(** -3 5) → -243
(** 3 -4) → 1/81
(** 3.7 -4) → 0.005335720890574502
(** 2/3 7) → 128/2187
(lib 'bigint)
(** 666 42) →
38540524895511613165266748863173814985473295063157418576769816295283207864908351682948692085553606681763707358759878656
|
http://rosettacode.org/wiki/Executable_library | Executable library | The general idea behind an executable library is to create a library
that when used as a library does one thing;
but has the ability to be run directly via command line.
Thus the API comes with a CLI in the very same source code file.
Task detail
Create a library/module/dll/shared object/... for a programming language that contains a function/method called hailstone that is a function taking a positive integer and returns the Hailstone sequence for that number.
The library, when executed directly should satisfy the remaining requirements of the Hailstone sequence task:
2. Use the routine to show that the hailstone sequence for the number 27 has 112 elements starting with 27, 82, 41, 124 and ending with 8, 4, 2, 1
3. Show the number less than 100,000 which has the longest hailstone sequence together with that sequence's length.
Create a second executable to calculate the following:
Use the library's hailstone function, in the standard manner, (or document how this use deviates from standard use of a library), together with extra code in this executable, to find the hailstone length returned most often for 1 ≤ n < 100,000.
Explain any extra setup/run steps needed to complete the task.
Notes:
It is assumed that for a language that overwhelmingly ships in a compiled form, such as C, the library must also be an executable and the compiled user of that library is to do so without changing the compiled library. I.e. the compile tool-chain is assumed not to be present in the runtime environment.
Interpreters are present in the runtime environment. | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | hailstone[1] = {1};
hailstone[n_] :=
hailstone[n] = Prepend[hailstone[If[EvenQ[n], n/2, 3 n + 1]], n];
If[$ScriptCommandLine[[1]] == $Input,
val = hailstone[27];
Print["hailstone(27) starts with ", val[[;; 4]], ", ends with ",
val[[-4 ;;]], ", and has length ", Length[val], "."];
val = MaximalBy[Range[99999], Length@*hailstone][[1]];
Print[val, " has the longest hailstone sequence with length ",
Length[hailstone[val]], "."]]; |
http://rosettacode.org/wiki/Executable_library | Executable library | The general idea behind an executable library is to create a library
that when used as a library does one thing;
but has the ability to be run directly via command line.
Thus the API comes with a CLI in the very same source code file.
Task detail
Create a library/module/dll/shared object/... for a programming language that contains a function/method called hailstone that is a function taking a positive integer and returns the Hailstone sequence for that number.
The library, when executed directly should satisfy the remaining requirements of the Hailstone sequence task:
2. Use the routine to show that the hailstone sequence for the number 27 has 112 elements starting with 27, 82, 41, 124 and ending with 8, 4, 2, 1
3. Show the number less than 100,000 which has the longest hailstone sequence together with that sequence's length.
Create a second executable to calculate the following:
Use the library's hailstone function, in the standard manner, (or document how this use deviates from standard use of a library), together with extra code in this executable, to find the hailstone length returned most often for 1 ≤ n < 100,000.
Explain any extra setup/run steps needed to complete the task.
Notes:
It is assumed that for a language that overwhelmingly ships in a compiled form, such as C, the library must also be an executable and the compiled user of that library is to do so without changing the compiled library. I.e. the compile tool-chain is assumed not to be present in the runtime environment.
Interpreters are present in the runtime environment. | #Nanoquery | Nanoquery | def hailstone(n)
seq = list()
while (n > 1)
append seq n
if (n % 2)=0
n = int(n / 2)
else
n = int((3 * n) + 1)
end
end
append seq n
return seq
end
if main
h = hailstone(27)
println "hailstone(27)"
println "total elements: " + len(hailstone(27))
print h[0] + ", " + h[1] + ", " + h[2] + ", " + h[3] + ", ..., "
println h[-4] + ", " + h[-3] + ", " + h[-2] + ", " + h[-1]
max = 0
maxLoc = 0
for i in range(1,99999)
result = len(hailstone(i))
if (result > max)
max = result
maxLoc = i
end
end
print "\nThe number less than 100,000 with the longest sequence is "
println maxLoc + " with a length of " + max
end |
http://rosettacode.org/wiki/Executable_library | Executable library | The general idea behind an executable library is to create a library
that when used as a library does one thing;
but has the ability to be run directly via command line.
Thus the API comes with a CLI in the very same source code file.
Task detail
Create a library/module/dll/shared object/... for a programming language that contains a function/method called hailstone that is a function taking a positive integer and returns the Hailstone sequence for that number.
The library, when executed directly should satisfy the remaining requirements of the Hailstone sequence task:
2. Use the routine to show that the hailstone sequence for the number 27 has 112 elements starting with 27, 82, 41, 124 and ending with 8, 4, 2, 1
3. Show the number less than 100,000 which has the longest hailstone sequence together with that sequence's length.
Create a second executable to calculate the following:
Use the library's hailstone function, in the standard manner, (or document how this use deviates from standard use of a library), together with extra code in this executable, to find the hailstone length returned most often for 1 ≤ n < 100,000.
Explain any extra setup/run steps needed to complete the task.
Notes:
It is assumed that for a language that overwhelmingly ships in a compiled form, such as C, the library must also be an executable and the compiled user of that library is to do so without changing the compiled library. I.e. the compile tool-chain is assumed not to be present in the runtime environment.
Interpreters are present in the runtime environment. | #NetRexx | NetRexx | $ jar cvfe RHailstoneSequence.jar RHailstoneSequence RHailstoneSequence.class
added manifest
adding: RHailstoneSequence.class(in = 2921) (out= 1567)(deflated 46%) |
http://rosettacode.org/wiki/Extreme_floating_point_values | Extreme floating point values | The IEEE floating point specification defines certain 'extreme' floating point values such as minus zero, -0.0, a value distinct from plus zero; not a number, NaN; and plus and minus infinity.
The task is to use expressions involving other 'normal' floating point values in your language to calculate these, (and maybe other), extreme floating point values in your language and assign them to variables.
Print the values of these variables if possible; and show some arithmetic with these values and variables.
If your language can directly enter these extreme floating point values then show it.
See also
What Every Computer Scientist Should Know About Floating-Point Arithmetic
Related tasks
Infinity
Detect division by zero
Literals/Floating point
| #Seed7 | Seed7 | $ include "seed7_05.s7i";
include "float.s7i";
const proc: main is func
begin
writeln("positive infinity: " <& Infinity);
writeln("negative infinity: " <& -Infinity);
writeln("negative zero: " <& -0.0);
writeln("not a number: " <& NaN);
# some arithmetic
writeln("+Infinity + 2.0 = " <& Infinity + 2.0);
writeln("+Infinity - 10.1 = " <& Infinity - 10.1);
writeln("+Infinity + -Infinity = " <& Infinity + -Infinity);
writeln("0.0 * +Infinity = " <& 0.0 * Infinity);
writeln("1.0/-0.0 = " <& 1.0 / -0.0);
writeln("NaN + 1.0 = " <& NaN + 1.0);
writeln("NaN + NaN = " <& NaN + NaN);
# some comparisons
writeln("NaN = NaN = " <& NaN = NaN);
writeln("isNaN(NaN) = " <& isNaN(NaN));
writeln("0.0 = -0.0 = " <& 0.0 = -0.0);
writeln("isNegativeZero(-0.0) = " <& isNegativeZero(-0.0));
writeln("isNegativeZero(0.0) = " <& isNegativeZero(0.0));
end func; |
http://rosettacode.org/wiki/Extreme_floating_point_values | Extreme floating point values | The IEEE floating point specification defines certain 'extreme' floating point values such as minus zero, -0.0, a value distinct from plus zero; not a number, NaN; and plus and minus infinity.
The task is to use expressions involving other 'normal' floating point values in your language to calculate these, (and maybe other), extreme floating point values in your language and assign them to variables.
Print the values of these variables if possible; and show some arithmetic with these values and variables.
If your language can directly enter these extreme floating point values then show it.
See also
What Every Computer Scientist Should Know About Floating-Point Arithmetic
Related tasks
Infinity
Detect division by zero
Literals/Floating point
| #Sidef | Sidef | var inf = 1/0 # same as: Inf
var nan = 0/0 # same as: NaN
var exprs = [
"1.0 / 0.0", "-1.0 / 0.0", "0.0 / 0.0", "- 0.0",
"inf + 1", "5 - inf", "inf * 5", "inf / 5", "inf * 0",
"1.0 / inf", "-1.0 / inf", "inf + inf", "inf - inf",
"inf * inf", "inf / inf", "inf * 0.0", " 0 < inf", "inf == inf",
"nan + 1", "nan * 5", "nan - nan", "nan * inf", "- nan",
"nan == nan", "nan > 0", "nan < 0", "nan == 0", "0.0 == -0.0",
]
exprs.each { |expr|
"%15s => %s\n".printf(expr, eval(expr))
}
say "-"*40
say("NaN equality: ", NaN == nan)
say("Infinity equality: ", Inf == inf)
say("-Infinity equality: ", -Inf == -inf)
say "-"*40
say("sqrt(-1) = ", sqrt(-1))
say("tanh(-Inf) = ", tanh(-inf))
say("(-Inf)**2 = ", (-inf)**2)
say("(-Inf)**3 = ", (-inf)**3)
say("acos(Inf) = ", acos(inf))
say("atan(Inf) = ", atan(inf))
say("log(-1) = ", log(-1))
say("atanh(Inf) = ", atanh(inf)) |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.