#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using P = pair<int, int>;
using T = tuple<int, int, int>;
#define al(a) a.begin(), a.end()
#define ral(a) a.rbegin(), a.rend()
#define sz(a) (int)a.size()
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rrep(i, n) for (int i = 1; i <= (n); ++i)
#define drep(i, n) for (int i = (n)-1; i >= 0; --i)
#define db(a, b) cout << #a << ": " << a << " " << #b << ": " << b << endl;

int main() {
  int n, x;
  cin >> n >> x;
  vector<int> a(n);
  rep(i, n) cin >> a[i];

  map<int, int> mp;
  rep(i, n) mp[a[i]]++;

  ll ans = 0;
  rep(i, n) ans += mp[x - a[i]];
  cout << ans << endl;
  return 0;
}