#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;
}

#include <bits/stdc++.h>
#include<algorithm>
using namespace std;
long long a[1000005],n,m,sum;
int main(){
	cin>>n>>m;
	for(int i=1;i<=n;i++){
		cin>>a[i]; 
	} 
	 
	for(int i=1;i<=n;i++){
		for(int j=1;j<=n;j++){
			if(a[i]-a[j]==m){
				sum++;
			}
		}
	}
	cout<<sum;


}
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