#include<bits/stdc++.h>
#define rep(i,a,b) for(int i=int(a);i<int(b);++i)
using namespace std;
typedef long long ll;
int INF = (1LL << 30) - 1;
int MOD = 1e9+7;
main(){
    int N,X;
    cin >> N >> X;
    ll cnt[200010] = {};
    if(X > 200000){
        cout << 0 << endl;
        return 0;
    }
    rep(i,0,N){
        int a;
        cin >> a;
        cnt[a]++;
    }
    ll ans = 0;
    rep(i,0,X+1){
        ans += cnt[i] * cnt[X - i];
    }
    cout << ans << endl;

}