#include <bits/stdc++.h>
#define int long long
using namespace std;
const int N = 2e5 + 10;
const int INF = 0x3f3f3f3f;
int n , m , a [N] , ans;

signed main()
{
	    cin >> n >> m;
	    for (int i = 0; i < n; i++)
	    {
	    	cin >> a [i];
		}
		sort (a , a + n);
		for (int i = 0; i < n - 1; i++)
		{
			for (int j = i + 1; j < n; j++)
			    if (a[j] - a [i] == m)
			        ans++;
			        //ans += (lower_bound (a + 1, a + n + 1 , a [j]) - upper_bound (a + 1, a + n + 1 , a [j])) * (lower_bound (a + 1, a + n + 1 , a [i]) - upper_bound (a + 1, a + n + 1 , a [i]));
		}
		cout << ans;
		return 0;
}