#include <fstream>
#include <unordered_map>
#define DIM 1025
using namespace std;
ifstream fin("oite.in");
ofstream fout("oite.out");
int n,s,sol,v[DIM];
unordered_map<int,int> f;
int main() {
    fin>>n>>s;
    for (int i=1;i<=n;i++)
        fin>>v[i];
    for (int i=1;i<n;i++) {
        for (int j=i+1;j<=n;j++) {
            int nr=s-v[i]-v[j];
            if (f.count(nr)!=0)
                sol+=f[nr];
        }
        for (int j=1;j<i;j++)
            f[v[i]+v[j]]++;
    }
    fout<<sol;
    return 0;
}