#include <iostream>
#include <algorithm>
#include <vector>
#include <cmath>
#include <map>

using namespace std;

int main() {
  int n, x;
  cin >> n >> x;
  map<int, int> mp;
  long long ans = 0;
  for (int i = 0; i < n; i++) {
    int a;
    cin >> a;
    if (a * 2 == x) ans++;
    ans += mp[x - a] * 2;
    mp[a]++;
  }
  cout << ans << endl;
}