#include<bits/stdc++.h>
using namespace std;


int main()
{
    int n, c, count=0;
    scanf("%d %d", &n, &c);
    vector<int> a(n); 
    for (int i = 0; i < n; i++) {
        scanf("%d", &a[i]);
    }
    sort(a.begin(), a.end());
    int left = 0, right = n-1;
    while(right>=0){
        while(left<right){
            if(a[right]-a[left]==c){
                count++;
            }
            if(a[right]-a[left]<c) break;
            left++;
        }
        left=0;
        right--;
    }
    printf("%d", count);
    return 0;
}