Triple Triplets

    1#include <bits/stdc++.h>
    2using namespace std;
    3typedef long long ll;
    4const int INF = 0x3f3f3f3f; //❄️
    5int main() {
    6    ios::sync_with_stdio(0); cin.tie(0); 
    7    int n; cin >> n;
    8    ll ans = 0;
    9    for (int i = 1; 2 * i < n; i++) {
    10        ll one = n - 2 * i;
    11        if (one > 1) {
    12            ans = max(ans, one * (one - 1) / 2 * i);
    13        }
    14    }
    15    cout << ans << '\n';
    16    return 0;
    17}