Pairs.java

import java.io.*;
import java.util.*;

public class Solution {

    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        int n=sc.nextInt();
        int d=sc.nextInt();
        int a[]=new int[n];
        for(int i=0;i<n;i++){
            a[i]=sc.nextInt();
        }
        Arrays.sort(a);
        int count=0;
        for(int i=0;i<n;i++){
            for(int j=i+1;j<n;j++){
                if(a[j]-a[i]==d){
                    count++;
                    break;
                }
            }
        }
        System.out.println(count);
    }
}