include <bits/stdc++.h>

using namespace std;
int n, m, a[1000005], res, d[1000005];
int main() {
cin >> n >> m;
for ( int i = 1; i <= n; i++ ) {
cin >> a[i];
d[a[i]]++;
}
sort ( a + 1, a + 1 + n );
for ( int i = n; i >1; i-- ) {
res=res+ upper_bound ( a + 1, a + i, m - a[i] )-a-1;
}
cout<<res;
}