#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define llong long long

int main() {
    int n, x;
    cin >> n >> x;
    map<int, int> a;
    set<int> keys;
    rep(i, n) {
        int val;
        cin >> val;
        if(a.count(val)) a[val]++;
        else a[val] = 1;
        keys.insert(val);
    }

    llong result = 0LL;
    for(pair<int, int> p: a) {
        if(p.first > x) break;
        if(a.count(x - p.first)) {
            result += (llong)a[p.first] * a[x - p.first];
        }
    }

    cout << result << "\n";
}