#include<algorithm>
#include<cmath>
#include<cstdio>
#include<functional>
#include<iomanip>
#include<iostream>
#include<map>
#include<queue>
#include<set>
#include<string>
#include<utility>
#include<vector>

using namespace std;
typedef long long ll;
const ll mod = 1000000007;
#define rep(i,n) for(int i=0;i<n;i++)
#define repl(i,s,e) for(int i=s;i<e;i++)
#define reple(i,s,e) for(int i=s;i<=e;i++)
#define revrep(i,n) for(int i=n-1;i>=0;i--)
#define all(x) (x).begin(),(x).end()

int main()
{	
	ll N, X;
	cin >> N >> X;

	vector<ll> A(N);
	rep(i, N)
	{
		cin >> A[i];
	}


	sort(all(A));


	ll count = 0;

	for (auto a : A)
	{
		auto l = lower_bound(all(A), X - a);
		auto u = upper_bound(all(A), X - a);

		count += distance(l, u);
	}

	cout << count << endl;

	return 0;
}