#include<iostream>
#include<fstream>
#include<cmath>
#include<cstdlib>
#include<algorithm>

using namespace std;

int n,c,num[200001],ans;
bool f[200001];

int main()
{
	int i,j,k;
	ifstream fin("dec.in");
	ofstream fout("dec.out");
	fin>>n>>c;
	j=0;
	for(i=1;i<=n;i++)
	{
		fin>>k;
		if(!f[k])
		{
			j++;
			num[j]=k;
			f[k]=true;
		}
	}
	n=j;
	sort(num+1,num+1+n);
	for(i=1;i<=n;i++)
		for(j=1;j<=n;j++)
		{
			if(i!=j&&(abs(num[i]-num[j])<c))
				continue;
			if(i!=j&&(abs(num[i]-num[j])==c))
				ans++;
			if(i!=j&&(abs(num[i]-num[j])>c))
				break;
		}
	fout<<ans<<endl;
	fin.close();
	fout.close();
	return 0;
}