#include <iostream>
#include <algorithm>
using namespace std;
const int M = 2e5 + 10;
int a[M];
long long  cnt = 0;

int main() {
	int p1 = 1, p2 = 1;//p2为第一个指针指向满足要求的第一个数字的下标，p1为第二个指针，指向满足要求的最后一个数字的下一个数字的下标
	int N, C;
	cin >> N >> C;
	for (int i = 1; i <= N; i++)
		cin >> a[i];
	sort(a + 1, a + 1 + N);
	for (int i = 1; i <= N; i++) 
	{
		p1 = p2 = i;
		while (p1 <= N && a[p1] - a[i] <= C)
			p1++;
		while (p2 <= N && a[p2] - a[i] < C)
			p2++;
		if (a[p2] - a[i] == C && a[p1 - 1] - a[i] == C && p1 - p2 >= 1)
			cnt += p1 - p2;//p1和p2之间的所有数字均满足条件
	}
	cout << cnt;
	return 0;
}