//=================================
// Created on: 2018/08/03 22:45:10
//=================================
#include <bits/stdc++.h>
#define show(x) std::cerr << #x << " = " << x << std::endl
using ll = long long;
using ld = long double;
constexpr ll MOD = 1000000007LL;
template <typename T>
constexpr T INF = std::numeric_limits<T>::max() / 10;
std::mt19937 mt{std::random_device{}()};
int main()
{
    int N, X;
    std::cin >> N >> X;
    std::vector<int> A(N);
    for (int i = 0; i < N; i++) { std::cin >> A[i]; }
    std::sort(A.begin(), A.end());
    ll ans = 0;
    for (int i = 0; i < N; i++) {
        const int D = X - A[i];
        ans += std::upper_bound(A.begin(), A.end(), D) - std::lower_bound(A.begin(), A.end(), D);
    }
    std::cout << ans << std::endl;
    return 0;
}