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

int main() {
	int n,k; cin >> n >> k;
	vector<int> arr(n);
	for(int i = 0; i < n; i++)
	cin >> arr[i];
	
	unordered_map<int,int> mp;
	int cnt = 0;
	for(int i = 0; i < n; i++){
		mp[arr[i]]++;
	}
	for(auto it : mp){
		int val = it.first;
		int req = val - k;
		if(mp.find(req) != mp.end())
		cnt++;
	}
	cout << cnt;
	return 0;
}