import java.util.*;

public class Solution {

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

import java.io.*;
import java.math.*;
import java.security.*;
import java.text.*;
import java.util.*;
import java.util.concurrent.*;
import java.util.function.*;
import java.util.regex.*;
import java.util.stream.*;
import static java.util.stream.Collectors.joining;
import static java.util.stream.Collectors.toList;

class Result {

    /*
     * Complete the 'pairs' function below.
     *
     * The function is expected to return an INTEGER.
     * The function accepts following parameters:
     *  1. INTEGER k
     *  2. INTEGER_ARRAY arr
     */

    public static int pairs(int k, List<Integer> arr) {
    // Write your code here
  Set<Integer> set = new HashSet<>();
        int count = 0;
        for (int num : arr) {
            if (set.contains(num - k)) count++;
            if (set.contains(num + k)) count++;
            set.add(num);
        }
        return count;
    }
    }

public class Solution {
    public static void main(String[] args) throws IOException {
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(System.getenv("OUTPUT_PATH")));

        String[] firstMultipleInput = bufferedReader.readLine().replaceAll("\\s+$", "").split(" ");

        int n = Integer.parseInt(firstMultipleInput[0]);

        int k = Integer.parseInt(firstMultipleInput[1]);

        List<Integer> arr = Stream.of(bufferedReader.readLine().replaceAll("\\s+$", "").split(" "))
            .map(Integer::parseInt)
            .collect(toList());

        int result = Result.pairs(k, arr);

        bufferedWriter.write(String.valueOf(result));
        bufferedWriter.newLine();

        bufferedReader.close();
        bufferedWriter.close();
    }
}

int comp(const void *a, const void *b) {
    return (*(int*)b - *(int*)a);
}

int pairs(int k, int arr_count, int* arr) {
    int p1 = 0;
    int p2 = 1;
    int count = 0;
    qsort(arr, arr_count, sizeof(int), comp);
    while(p2 < arr_count) {
        long long d = arr[p1] - arr[p2];
        ++p2;
        if(d == k) ++count;
        else if (d > k || p2 >= arr_count) {
            ++p1;
            p2 = p1 + 1;
        }
    }
    return count;
}

sub pairs {
    my $k = shift;
    my $arr = shift;
    my $res = 0;

    my %h = map {$_ => 1} @$arr;
    foreach my $key (keys %h) {
        $res++ if (exists($h{$k + $key}));
    }

    return $res;
}