#include<cstdio>
#include<queue>
#include<utility>
#include<cstring>
#include<stack>
#include<algorithm>
#include<cmath>
#include<iostream>
#include<map>
#define MAX_N 100001
#define INF_INT 2147483647
#define INF_LL 9223372036854775807
#define REP(i,n) for(int i=0;i<(int)(n);i++)
using namespace std;
typedef long long int ll;
typedef pair<ll,ll> P;
bool cmp_P(const P &a,const P &b){
  return a.second < b.second;
}
int main()
{
  ll N,X,res=0;
  cin >> N >> X;
  vector<ll> a(N+1);
  map<ll,ll> mp;
  REP(i,N){
    cin >> a[i];
    mp[a[i]]++;
  }
  REP(i,N){
    res += mp[X-a[i]];
  }
  cout << res << endl;
  return 0;
}