#include <bits/stdc++.h>
#define rep(i,n) for(int i=0;i<n;i++)
using namespace std;
using ll =  long long ;
using P = pair<int,int> ;
const int INF = 1e9;
const int MOD = 1000000007;

int main(){
    int n;
    cin >> n;
    int x;
    cin >> x;
    vector<int> a(n);
    rep(i,n) cin >> a[i];
    sort(a.begin(),a.end());
    ll ans = 0;
    rep(i,n){
        int k = upper_bound(a.begin(),a.end(),x-a[i]) - lower_bound(a.begin(),a.end(),x-a[i]);
        ans += k;
    }
    cout << ans << endl;
    return 0;
}