Problem I. Inverse of sum

时间限制 3000 ms   内存限制 512 MB

There are $n$ nonnegative integers $a_{1…n}$ which are less than $p$. HazelFan wants to know how many pairs $i,j(1\leq i<j\leq n)$ are there, satisfying $\frac{1}{a_i+a_j}\equiv\frac{1}{a_i}+\frac{1}{a_j}$ when we calculate module $p$, which means the inverse element of their sum equals the sum of their inverse elements. Notice that zero element has no inverse element.
 

输入数据

The first line contains a positive integer $T(1\leq T\leq5)$, denoting the number of test cases.
For each test case:
The first line contains two positive integers $n,p(1\leq n\leq10^5,2\leq p\leq10^{18})$, and it is guaranteed that $p$ is a prime number.
The second line contains $n$ nonnegative integers $a_{1...n}(0\leq a_i<p)$.
 

输出数据

For each test case:
A single line contains a nonnegative integer, denoting the answer.
 

样例输入

复制
2
5 7
1 2 3 4 5
6 7
1 2 3 4 5 6

样例输出

复制
4
6

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