代码如下

/*
 * @Descripttion: c_a
 * @version: 1.0
 * @Author: sb
 * @Date: 2021-08-26 19:31:02
 * @LastEditors: sb
 * @LastEditTime: 2021-09-12 06:52:31
 */
#include<bits/stdc++.h>
using namespace std;
int k[200001],c,q[200001],sum,a=100003;
int main()
{
    int n;
    scanf("%d %d",&n,&c);
    for(int i=1;i<=n;i++)
    {
        int u=0;
        scanf("%d",&u);
        k[u%a]+=1;
        q[u%a+c%a]+=1;
    }
    for(int i=1;i<=100003;i++)
    {
        sum+=k[i]*q[i];
    }
    cout<<sum;
    return 0;
}