#include <bits/stdc++.h>
// #include <atcoder/all>
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define REP(i, st, n) for (int i = st; i < (n); ++i)
#define rrep(i, n) for (int i = (n - 1); i >= 0; --i)
#define RREP(i, ed, n) for (int i = (n - 1); i >= (ed); --i)
#define BIT(n, k) ((n >> k) & 1)
#define LEN(s) (int)s.size()
#define popcount(n) __builtin_popcount(n)
#define RANGE(a) a.begin(), a.end()
#define RRANGE(a) a.rbegin(), a.rend()
#define chmax(a, b) a = max(a, b)
#define chmin(a, b) a = min(a, b)
#define dump(x) cout << #x << " = " << x << endl
#define myceil(a, b) (a + (b - 1)) / (b)
#define pow2(a) ((a) * (a))
using namespace std;
using ll = int64_t;
using P = pair<ll, ll>;
template <class T>
using V = vector<T>;
const int IINF = 1e8;
const ll LINF = 1e15;
const ll mod = 1e9 + 7;
template <typename T>
istream& operator>>(istream& i, V<T>& v) {
  rep(j, LEN(v)) i >> v[j];
  return i;
}
istream& operator>>(istream& i, P& p) {
  i >> p.first >> p.second;
  return i;
}
template <typename T>
ostream& operator<<(ostream& o, V<T>& v) {
  rep(i, LEN(v)) o << v[i] << " ";
  return o;
}
ostream& operator<<(ostream& o, P p) {
  o << p.first << " " << p.second;
  return o;
}

/**
 * @brief Binary Indexed Tree
 * @note 0-indexed
 */
template <typename T>
class BinaryIndexdTree {
 public:
  int n;
  vector<T> data;
  BinaryIndexdTree(int n_) : n(n_), data(n_ + 1, 0) {}
  // i 番目に x を加算
  void add(int i, T x) {
    for (; i < n; i |= i + 1) data[i] += x;
  }
  // [left, right) の和
  T sum(int left, int right) { return sum(right) - sum(left); }
  // [0, i) の和
  T sum(int i) {
    T ret(0);
    for (i--; i >= 0; i = (i & (i + 1)) - 1) {
      ret += data[i];
    }
    return ret;
  }
};

int main() {
  int n;
  ll x;
  cin >> n >> x;
  V<int> a(n);
  cin >> a;

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

  ll ans = 0;
  rep(i, n) {
    ll tgt = x - a[i];
    if (mp.find(tgt) != mp.end()) {
      ans += mp[tgt];
    }
  }
  cout << ans << endl;
}