#include <bits/stdc++.h>

#define Nmax 1030
#define ll long long

using namespace std;

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

int N, L;
int A[Nmax];
vector < pair <int, int> > H[1003491];
ll ans = 0;

int getKey(int P)
{
    return P % 1003491;
}

int CNT(int P)
{
    int key = getKey(P);
    for(auto it : H[key])
        if(it.first == P)
            return it.second;
    return 0;
}

void ins(int P, int v)
{
    int key = getKey(P);
    for(auto &it : H[key])
        if(it.first == P)
        {
            it.second += v;
            return;
        }
    H[key].push_back(make_pair(P, v));
}

int main()
{
    fin >> N >> L;
    for(int i = 1; i <= N; i++)
        fin >> A[i];
    for(int i = 1; i <= N; i++)
    {
        for(int j = i + 1; j <= N; j++)
            if(L >= A[i] + A[j])
                ans += CNT(L - A[i] - A[j]);
        for(int j = i - 1; j >= 1; j--)
            ins(A[i] + A[j], 1);
    }
    fout << ans << "\n";
    return 0;
}