#include<iostream>
#include<cstdlib>
#include<cstdio>
using namespace std;
int n,w[100000],ji=0;
long long m,q[210000],answer=0;

//void jia();
int main()
{
	freopen ("dec.in","r",stdin);
	freopen ("dec.out","w",stdout);
	scanf("%d%d",&n,&m);
	for (int i=1;i<=n;i++)
	{
		cin>>q[i];
	}
	for (int i=1;i<=n;i++)
	{
		for (int j=i+1;j<=n;j++)
		{
			if (abs(q[i]-q[j])==m)
			{
				answer++;
			}
		}
	}
	cout<<answer;
	return 0;
}
/*
void jia()
{
	int jin[100000]={0};
	jin[0]=1;
	for (int i=0;i<=ji;i++)
	{
		if (w[i]+jin[i]>=10)
		{
			w[i]+=jin[i];
			w[i+1]++;
			if (i==ji)
			{
				ji++;
			}
		}
		else
		{
			w[i]+=jin[i];
		}
	}
}
*/