#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <map>
#include <cstdio>
#include <cstring>
#include <cmath>
using namespace std;
using ll = long long;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);

    int n, x;
    cin >> n >> x;

    int m = 100001;
    vector<int> b(m);
    for (int i = 0; i < n; i++) {
        int a;
        cin >> a;
        b[a]++;
    }

    ll r = 0;
    for (int i = 0; i < m; i++) {
        int j = x - i;
        if (0 <= j && j < m) {
            r += (ll)b[i] * b[j];
        }
    }

    cout << r << endl;

    return 0;
}