#include <fstream>
#include <vector>
#define MOD 666013
using namespace std;
ifstream fin ("oite.in");
ofstream fout ("oite.out");
int N, L, sol, V[1100];
vector < pair < int, int > > H[MOD + 16];

bool Find_H(int p, int val)
{
    for (int i = 0; i < H[p].size(); i++)
    {
        if (H[p][i].first == val)
        {
            H[p][i].second += 1;
            return 1;
        }
    }
    return 0;
}

int main()
{
    fin >> N >> L;
    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 sum = L - (V[i] + V[j]);
            if (sum < 0) continue;
            int poz = sum % MOD;
            for (int k = 0; k < H[poz].size(); k++)
            {
                if (sum == H[poz][k].first) {
                    sol += H[poz][k].second;
                    break;
                }
            }
        }
        for (int j = i - 1; j >= 1; j--)
        {
            int sum = V[i] + V[j];
            int poz = sum % MOD;
            if (Find_H(poz, sum)) continue;
            H[poz].push_back( { sum, 1 } );
        }
    }

    fout << sol << '\n';
    fout.close();
    return 0;
}