text
stringlengths 0
801
|
---|
There are $n$ planets in the universe. Each planet has an interval of vulnerability $[l, r]$, during which it will be exposed to destruction by orangutans. Orangutans can also expand the interval of vulnerability of any planet by $1$ unit. |
Specifically, suppose the expansion is performed on planet $p$ with interval of vulnerability $[l_p, r_p]$. Then, the resulting interval of vulnerability may be either $[l_p - 1, r_p]$ or $[l_p, r_p + 1]$. |
Given a set of planets, orangutans can destroy all planets if the intervals of vulnerability of all planets in the set intersect at least one common point. Let the score of such a set denote the minimum number of expansions that must be performed. |
Orangutans are interested in the sum of scores of all non-empty subsets of the planets in the universe. As the answer can be large, output it modulo $998\,244\,353$. |
The first line contains an integer $t$ ($1 \leq t \leq 10^4$) — the number of test cases. |
The first line of each test case contains an integer $n$ ($1 \leq n \leq 10^6$) — the number of planets in the universe. |
The following $n$ lines contain two integers $l_i$ and $r_i$ ($1 \leq l_i \leq r_i \leq n$) — the initial interval of vulnerability of the $i$-th planet. |
It is guaranteed that the sum of $n$ does not exceed $10^6$ over all test cases. |
For each test case, output an integer — the sum of scores to destroy all non- empty subsets of the planets in the universe, modulo $998\,244\,353$. |
In the first testcase, there are seven non-empty subsets of planets we must consider: |
* For each of the subsets $\\{[1,1]\\}, \\{[2,3]\\}, \\{[3,3]\\}$, the score is $0$. * For the subset $\\{[2,3], [3,3]\\}$, the score is $0$, because the point $3$ is already contained in both planets' interv |
You are given an array $a = [1, 2, \ldots, n]$, where $n$ is odd, and an integer $k$. |
Your task is to choose an odd positive integer $m$ and to split $a$ into $m$ subarrays$^{\dagger}$ $b_1, b_2, \ldots, b_m$ such that: |
* Each element of the array $a$ belongs to exactly one subarray. * For all $1 \le i \le m$, $|b_i|$ is odd, i.e., the length of each subarray is odd. * $\operatorname{median}([\operatorname{median}(b_1), \operatorname{median}(b_2), \ldots, \operatorname{median}(b_m)]) = k$, i.e., the median$^{\ddagger}$ of the array of medians of all subarrays must equal $k$. $\operatorname{median}(c)$ denotes the median of the array $c$. |
$^{\dagger}$A subarray of the array $a$ of length $n$ is the array $[a_l, a_{l + 1}, \ldots, a_r]$ for some integers $1 \le l \le r \le n$. |
$^{\ddagger}$A median of the array of odd length is the middle element after the array is sorted in non-decreasing order. For example: $\operatorname{median}([1,2,5,4,3]) = 3$, $\operatorname{median}([3,2,1]) = 2$, $\operatorname{median}([2,1,2,1,2,2,2]) = 2$. |
Each test consists of multiple test cases. The first line contains a single integer $t$ ($1 \le t \le 5000$) — the number of test cases. The description of the test cases follows. |
The first line of each test case contains two integers $n$ and $k$ ($1 \le k \le n < 2 \cdot 10^5$, $n$ is odd) — the length of array $a$ and the desired median of the array of medians of all subarrays. |
It is guaranteed that the sum of $n$ over all test cases does not exceed $2 \cdot 10^5$. |
For each test case: |
* If there is no suitable partition, output $-1$ in a single line. * Otherwise, in the first line, output an odd integer $m$ ($1 \le m \le n$), and in the second line, output $m$ distinct integers $p_1, p_2 , p_3 , \ldots, p_m$ ($1 = p_1 < p_2 < p_3 < \ldots < p_m \le n$) — denoting the left borders of each subarray. |
In detail, for a valid answer $[p_1, p_2, \ldots, p_m]$: |
* $b_1 = \left[ a_{p_1}, a_{p_1 + 1}, \ldots, a_{p_2 - 1} \right]$ * $b_2 = \left[ a_{p_2}, a_{p |
This is an interactive problem. |
Upon clearing the Waterside Area, Gretel has found a monster named Genokraken, and she's keeping it contained for her scientific studies. |
The monster's nerve system can be structured as a tree$^{\dagger}$ of $n$ nodes (really, everything should stop resembling trees all the time$\ldots$), numbered from $0$ to $n-1$, with node $0$ as the root. |
Gretel's objective is to learn the exact structure of the monster's nerve system — more specifically, she wants to know the values $p_1, p_2, \ldots, p_{n-1}$ of the tree, where $p_i$ ($0 \le p_i < i$) is the direct parent node of node $i$ ($1 \le i \le n - 1$). |
She doesn't know exactly how the nodes are placed, but she knows a few convenient facts: |
* If we remove root node $0$ and all adjacent edges, this tree will turn into a forest consisting of only paths$^{\ddagger}$. Each node that was initially adjacent to the node $0$ will be the end of some path. * The nodes are indexed in a way that if $1 \le x \le y \le n - 1$, then $p_x \le p_y$. * Node $1$ has exactly two adjacent nodes (including the node $0$). |
| |  ---|---|--- The tree in this picture does not satisfy the condition, because if we remove node $0$, then node $2$ (which was initially adjacent to the node $0$) will not be the end of the path $4-2-5$.| The tree in this picture does not satisfy the condition, because $p_3 \le p_4$ must hold.| The tree in this picture does not satisfy the condition, because node $1$ has only one adjacent node. Gretel can make queries to the containment cell: |
* "? a b" ($1 \le a, b < n$, $a \ne b$) — the cell will check if the simple path between nodes $a$ and $b$ contains the node $0$. |
However, to avoid unexpected consequences by overstimulating the creature, Gretel wants to query at most $2n - 6$ times. Though Gretel is gifted, she can't do everything all at once, so can |
During her journey with Kosuke, Sakurako and Kosuke found a valley that can be represented as a matrix of size $n \times n$, where at the intersection of the $i$-th row and the $j$-th column is a mountain with a height of $a_{i,j}$. If $a_{i,j} < 0$, then there is a lake there. |
Kosuke is very afraid of water, so Sakurako needs to help him: |
* With her magic, she can select a square area of mountains and increase the height of each mountain on the main diagonal of that area by exactly one. |
More formally, she can choose a submatrix with the upper left corner located at $(i, j)$ and the lower right corner at $(p, q)$, such that $p-i=q-j$. She can then add one to each element at the intersection of the $(i + k)$-th row and the $(j + k)$-th column, for all $k$ such that $0 \le k \le p-i$. |
Determine the minimum number of times Sakurako must use her magic so that there are no lakes. |
The first line contains a single integer $t$ ($1 \le t \le 200$) — the number of test cases. |
Each test case is described as follows: |
* The first line of each test case consists of a single number $n$ ($1 \le n \le 500$). * Each of the following $n$ lines consists of $n$ integers separated by spaces, which correspond to the heights of the mountains in the valley $a$ ($-10^5 \le a_{i,j} \le 10^5$). |
It is guaranteed that the sum of $n$ across all test cases does not exceed $1000$. |
For each test case, output the minimum number of times Sakurako will have to use her magic so that all lakes disappear. |
Even in university, students need to relax. That is why Sakurakos teacher decided to go on a field trip. It is known that all of the students will be walking in one line. The student with index $i$ has some topic of interest which is described as $a_i$. As a teacher, you want to minimise the disturbance of the line of students. |
The disturbance of the line is defined as the number of neighbouring people with the same topic of interest. In other words, disturbance is the number of indices $j$ ($1 \le j < n$) such that $a_j = a_{j + 1}$. |
In order to do this, you can choose index $i$ ($1\le i\le n$) and swap students at positions $i$ and $n-i+1$. You can perform any number of swaps. |
Your task is to determine the minimal amount of disturbance that you can achieve by doing the operation described above any number of times. |
The first line contains one integer $t$ ($1\le t\le 10^4$) — the number of test cases. |
Each test case is described by two lines. |
* The first line contains one integer $n$ ($2 \le n \le 10^5$) — the length of the line of students. * The second line contains $n$ integers $a_i$ ($1\le a_i\le n$) — the topics of interest of students in line. |
It is guaranteed that the sum of $n$ across all test cases does not exceed $2\cdot 10^5$. |
For each test case, output the minimal possible disturbance of the line that you can achieve. |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.