#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <climits>
#include <cfloat>
#include <map>
#include <utility>
#include <set>
#include <iostream>
#include <memory>
#include <string>
#include <vector>
#include <algorithm>
#include <functional>
#include <sstream>
#include <complex>
#include <stack>
#include <queue>
#include <iomanip>
#include <array>
#include <numeric>
#include <regex>
#include <bitset>
#include <deque>

using namespace std;
typedef long long ll;
typedef pair<int, int> p_ii;

const int INF = 1e9;
const double PI = acos(-1.0);
const ll MOD = 1e9 + 7;


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

    ll res=0LL;

    for (int i = 0; i < n; i++) {
        int t = a[i];
        if(binary_search(a.begin(),a.end(),x-t)){
            res+=upper_bound(a.begin(),a.end(),x-t)-lower_bound(a.begin(),a.end(),x-t);
        }
    }
    cout<<res<<endl;

    return 0;
}