#include<bits/stdc++.h>
#define _for(i,a,b) for(int i=a;i<=b;i++)
#define __for(i,a,b) for(int i=a;i>=b;i--)
using namespace std;
const int maxn=2e5,mod=3e6+7;
int hashe[mod+1];
int n,c;
int a[maxn+10];
int main(int argc,char* argv[]){
	freopen("P1102_4.in","r",stdin);//freopen("xxxxxxxx.out","w",stdout);
	long long ans=0;
	scanf("%d %d",&n,&c);
	_for(i,1,n){
		scanf("%d",&a[i]);
		hashe[(a[i]%mod+mod)%mod]++;
	}
	_for(i,1,n){
		ans+=hashe[(a[i]%mod+c%mod+mod)%mod];
	}
	printf("%lld\n",ans);
	return 0;
	//fclose(stdin);fclose(stdout);
}