题目描述
Polycarp has two favorite integers $x$ and $y$ (they can be equal), and he has found an array $a$ of length $n$.
Polycarp considers a pair of indices $\langle i, j \rangle$ ($1 \le i < j \le n$) beautiful if:
- $a_i + a_j$ is divisible by $x$;
- $a_i - a_j$ is divisible by $y$.
For example, if $x=5$, $y=2$, $n=6$, $a=$[$1, 2, 7, 4, 9, 6$], then the only beautiful pairs are:
- $\langle 1, 5 \rangle$: $a_1 + a_5 = 1 + 9 = 10$ ($10$ is divisible by $5$) and $a_1 - a_5 = 1 - 9 = -8$ ($-8$ is divisible by $2$);
- $\langle 4, 6 \rangle$: $a_4 + a_6 = 4 + 6 = 10$ ($10$ is divisible by $5$) and $a_4 - a_6 = 4 - 6 = -2$ ($-2$ is divisible by $2$).
Input
The first line of the input contains a single integer $t$ ($1 \le t \le 10^4$) — the number of test cases. Then the descriptions of the test cases follow.
The first line of each test case contains three integers $n$, $x$, and $y$ ($2 \le n \le 2 \cdot 10^5$, $1 \le x, y \le 10^9$) — the size of the array and Polycarp's favorite integers.
The second line of each test case contains $n$ integers $a_1, a_2, \dots, a_n$ ($1 \le a_i \le 10^9$) — the elements of the array.
It is guaranteed that the sum of $n$ over all test cases does not exceed $2 \cdot 10^5$.
Output
For each test case, output a single integer — the number of beautiful pairs in the array $a$.
输入格式
见题面 Input 部分
输出格式
见题面 Output 部分