#include <bits/stdc++.h>
using namespace std;
ifstream f("oite.in");
ofstream g("oite.out");
unordered_map <long long,int> H;
int n,i,j,k;
long long a[1025],suma,sol;

int main()
{
    f>>n>>suma;
    for (i=1;i<=n;i++)
        f>>a[i];
    for (i=1;i<n;i++)
    {
        for (j=i+1;j<=n;j++)
            if (H[suma-a[i]-a[j]]) sol+=H[suma-a[i]-a[j]];
        for (j=1;j<i;j++)
            H[a[i]+a[j]]++;
    }

    g<<sol;

    return 0;
}