#include<bits/stdc++.h>
using namespace std;
#define int long long
#define MAXVAL 100000

signed main(){
	int N, X, a[MAXVAL+100] = {}, A, ans = 0;
	
	cin>>N>>X;
	
	for(int i = 1; i <= N; i++){
		cin>>A;
		a[A]++;
	}
		
	for(int i = 0; i <= X && i <= MAXVAL; i++)
		if(X-i <= MAXVAL) ans += a[i]*a[X-i];
		
	cout<<ans<<endl;
	
	return 0;
}