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#include <fstream>
#include <algorithm>
#include <unordered_map>
#include <vector>
using namespace std;
const int NMAX = 1024;
int v[NMAX + 3];
unordered_map <int, vector <int> > m;
unordered_map <int, vector <int> > :: iterator it, it2;
int main()
{
ifstream cin("oite.in");
ofstream cout("oite.out");
int n, s, i, j;
cin >> n >> s;
for (i = 1; i <= n; i++)
cin >> v[i];
int ans = 0;
for (i = 1; i + 1 <= n; i++)
for (j = i + 1; j <= n; j++)
{
int sum = v[i] + v[j];
m[sum].push_back(j);
int need = s - sum;
it = m.find(need);
if (it == m.end())
continue;
for (int k = 0; k < it->second.size(); k++)
if (it->second[k] < i)
ans++;
}
cout << ans;
}