#include <bits/stdc++.h>
using namespace std;

int main() {
    int64_t n, x;
    cin >> n >> x;
    vector<int64_t> as(n);
    for(auto&a:as){
        cin>>a;
    }
    sort(as.begin(),as.end());
    int64_t ans = 0;
    for(auto&a:as){
        int64_t b=x-a;
        ans+=distance(lower_bound(as.begin(),as.end(),b),upper_bound(as.begin(),as.end(),b))-(a==b);
    }
    cout<<ans<<endl;
    return 0;
}