A Never Ending Story [CODEWAR]

/// AVG TIME IN TEST-0: 1.25s, TEST-1: 1.68s

#include<bits/stdc++.h>
using namespace std;

#define ll  long long int

int main() {
    int tc = 0;
    int n;
    while(cin >> n)
    {
        vector<ll> vv(n);
        for (int i = 0; i < n; i++) scanf("%lld", &vv[i]);

        sort(vv.begin(), vv.end());
        ll cnt = 0;
        for(int i = 0; i<n; i++)
        {
            for(int j = i+1; j<n; j++)
            {
                ll sum = vv[i] + vv[j] - 1;
                ll k = upper_bound(vv.begin(), vv.end(), sum) - vv.begin() - 1;
                cnt += (k - j);
            }
        }
        printf("Case %d: %lld\n", ++tc, cnt);
    }
}