1.​​题目链接​​。找一下规律，其实看看看i,j,k的性质，发现最优的比例一般都是1:1:1或者1:1:2.

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#pragma warning(disable:4996)
int main()
{
  int T;
  scanf("%d", &T);
  while (T--)
  {
    ll n;
    scanf("%lld", &n);
    ll mmax = -1;
    if (n % 3 == 0)
    {
      ll tem = n / 3;
      mmax = max(tem*tem*tem, mmax);
    }
    if (n % 4 == 0)
    {
      ll tem1 = n / 2;
      ll tem2 = n / 4;
      mmax = max(mmax, tem1*tem2*tem2);
    }
    cout << mmax << endl;
  }
}