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

signed main() {
  ios::sync_with_stdio(false);

  int N, X;
  cin >> N >> X;

  vector<int> A(N);
  for (int i = 0; i < N; ++i) cin >> A[i];

  sort(A.begin(), A.end());

  long long ans = 0;
  for (int i = 0; i < N; ++i) {
    int lb = lower_bound(A.begin(), A.end(), X - A[i]) - A.begin();
    int rb = upper_bound(A.begin(), A.end(), X - A[i]) - A.begin();
    ans += rb - lb;
  }

  cout << ans << endl;

  return 0;
}