#include <bits/stdc++.h>
using namespace std;

#define ll long long
#define rep(i, n) for (ll i = 0; i < n; ++i)
#define rep_up(i, a, b) for (ll i = a; i < b; ++i)
#define rep_down(i, a, b) for (ll i = a; i > b; --i)

#define P pair<ll, ll>
#define Graph vector<vector<ll>>
#define fi first
#define se second

#define vvvvll vector<vector<vector<vector<ll>>>>
#define vvvll vector<vector<vector<ll>>>
#define vvll vector<vector<ll>>
#define vll vector<ll>

#define vvvvdo vector<vector<vector<vector<double>>>>
#define vvvdo vector<vector<vector<double>>>
#define vvdo vector<vector<double>>
#define vdo vector<double>

#define pqll priority_queue<ll>
#define pqllg priority_queue<ll, vector<ll>, greater<ll>>

constexpr ll INF = (1ll << 60);
// constexpr ll mod = 998244353;
constexpr ll mod = 1000000007;
constexpr double pi = 3.14159265358979323846;
template <typename T>
inline bool chmax(T &a, T b) {
    if (a < b) {
        a = b;
        return 1;
    }
    return 0;
}
template <typename T>
inline bool chmin(T &a, T b) {
    if (a > b) {
        a = b;
        return 1;
    }
    return 0;
}

void pt_vvll(vvll v) {
    ll vs = v.size(), vs0 = v[0].size();
    rep(i, vs) {
        rep(j, vs0) {
            if (v[i][j] != INF)
                cout << v[i][j];
            else
                cout << -1;

            if (j != vs0 - 1)
                cout << " ";
            else
                cout << "\n";
        }
    }
}
void pt_vll(vll v) {
    ll vs = v.size();
    rep(i, vs) {
        cout << v[i];
        if (i == vs - 1)
            cout << "\n";
        else
            cout << " ";
    }
}

bool debug_flg = 0;
int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    ll N, X;
    cin >> N >> X;
    vll a(N);
    rep(i, N) cin >> a[i];

    sort(a.begin(), a.end());
    ll ans = 0;
    rep(i, N) {
        ans += upper_bound(a.begin(), a.end(), X - a[i]) -
               lower_bound(a.begin(), a.end(), X - a[i]);
    }
    cout << ans << "\n";
    return 0;
}