#include <bits/stdc++.h>
using namespace std;

ifstream fin("oite.in");
ofstream fout("oite.out");

unordered_map<int, int> M;
int a[1026];

int main()
{
    int n, s, i, j, x, cnt = 0;
    fin >> n >> s;
    for (i = 1; i <= n; i++)
        fin >> a[i];
    sort(a + 1, a + n + 1);
    for (i = 1; i < n; i++)
    {
        for (j = i + 1; j <= n && s - a[i] - a[j] >= 0; j++)
        {
            x = s - a[i] - a[j];
            if (M.count(x) > 0)
                cnt += M[x];
        }
        for (j = 1; j < i; j++)
            M[a[i] + a[j]]++;
    }
    fout << cnt << "\n";
    return 0;
}