1425: Pair Sum and Perfect Square
[命题人 : ]
题目描述
A permutation of $n$ elements is an array of $n$ numbers from $1$ to $n$ such that each number occurs exactly one times in it.
Given a permutation $p$ of $n$ elements, there are $Q$ queries to be made.
Each query provides two integers $L$ and $R (1 ≤ L ≤ R ≤ n)$, asking how many pairs $(i, j)$ satisfy $L \leq i < j \leq R$ and $p_i + p_j$ is a square number.
A square number is the product of some integer with itself. For example, $9$ is a square number, since it can be written as $3^2$.
Given a permutation $p$ of $n$ elements, there are $Q$ queries to be made.
Each query provides two integers $L$ and $R (1 ≤ L ≤ R ≤ n)$, asking how many pairs $(i, j)$ satisfy $L \leq i < j \leq R$ and $p_i + p_j$ is a square number.
A square number is the product of some integer with itself. For example, $9$ is a square number, since it can be written as $3^2$.
输入
he first line contains an integer $T (T\leq 5)$, representing the number of test cases.
For each test case, the input consists of $Q+3$ lines:
The first line contains an integer $n (1 \leq n \leq 10^5)$, representing the length of permutation $p$.
The second line contains $n$ integers $p_1, p_2, ..., p_n (1 \leq p_i \leq n)$, representing the elements of permutation $p$.
The third line contains an integer $Q (1 \leq Q \leq 10^5)$, indicating the number of queries.
The next $Q$ lines each contain two integers $L$ and $R (1 \leq L \leq R \leq n)$, representing the range of each query.
For each test case, the input consists of $Q+3$ lines:
The first line contains an integer $n (1 \leq n \leq 10^5)$, representing the length of permutation $p$.
The second line contains $n$ integers $p_1, p_2, ..., p_n (1 \leq p_i \leq n)$, representing the elements of permutation $p$.
The third line contains an integer $Q (1 \leq Q \leq 10^5)$, indicating the number of queries.
The next $Q$ lines each contain two integers $L$ and $R (1 \leq L \leq R \leq n)$, representing the range of each query.
输出
For each query in each test case, output one line containing an integer, representing the answer.
样例输入 Copy
1
8
5 7 4 1 8 6 2 3
10
4 5
2 6
1 8
2 7
4 8
3 8
4 7
1 5
2 5
3 7
样例输出 Copy
1
1
5
2
3
3
1
2
1
1