//#include <bits/stdc++.h>

#include <iostream>
#include <algorithm>
#include <vector>
#include <string>
#include <cstring>
#include <complex>
#include <stack>
#include <queue>
#include <unordered_map>
#include <map>

#define INF 100000000
#define rep(i, a) for (int i = 0; i < (a); i++)
using namespace std;

int main() {
    int n, x;
    cin >> n >> x;

    vector<int> a(n);

    int i;
    for(i = 0; i < n; i++){
        cin >> a[i];
    }
    sort(a.begin(), a.end());

    long long int ans = 0;
    for(i = 0; i < n; i++){
        ans += upper_bound(a.begin(), a.end(), x-a[i]) - lower_bound(a.begin(), a.end(), x-a[i]);
    }

    cout << ans << endl;
}