#include<iostream>
#include<algorithm>
using namespace std;
const int N=200005;
long long  a[N];
int main()
{
	long long  n,c;
	cin>>n>>c;
	for(int i=1;i<=n;i++)cin>>a[i];
	sort(a+1,a+1+n);
	int l=1,r=1;
	long long sum=0;
	for(int k=1;k<=n;k++)
	{
		while(r<=n&&a[r]-a[k]<=c)r++;
		while(l<=n&&a[l]-a[k]<c)l++;
		sum+=r-l;
	}
	printf("%d",sum);
	
	
	
	
	return 0;
}

第三个wa了，为啥不行啊