include<bits/stdc++.h>
using namespace std;
int a[2000200];
int main() {
int n,c;
cin>>n>>c;
for(int i = 0;i < n;i ++)cin>>a[i];
sort(a,a + n);
long long cnt = 0;
for(int i = 0;i < n;i ++)
{
int l = i,r = n;
while(l < r)
{
int mid = (l+r)/2;
if(a[mid] - a[i] >= c)
{
r = mid;
}else l = mid + 1;
}
int l2 = i+1,r2 = n-1;
while(l2<r2)
{
int mid = (l2 + r2 + 1)/2;
if(a[mid]-a[i] <= c)
{
l2 = mid;
}else r2 = mid - 1;
}
if(a[r] - a[i] == c && a[l2] - a[i] == c)
{
cnt += r2 - r + 1;
}
}
cout<<cnt<<endl;
return 0;
}