#include<bits/stdc++.h> 
using namespace std;
const int N=1e5+10;
int a[N];
int findmax(int l, int r, int x)
{
    if(x < a[l]) return 0;
    while(l + 1 < r)
    {
        int mid = (l + r) >> 1;
        if(a[mid] <= x) l = mid;
        else r = mid;
    }
    return l;
}
int main()
{
    int n, K; scanf("%d%d", &n, &K);
    for(int i = 1; i <= n; i++) scanf("%d", &a[i]);
    a[++n] = 0;
    sort(a + 1, a + n + 1);
    long long ans = 0;
    for(int i = 2; i <= n; i++)
    {
        int p = findmax(1, i, K - a[i]); if(p == 0) break;
        ans += p;
    }
    printf("%lld\n", ans);
    return 0;
}