1165D - Almost All Divisors - CodeForces Solution

#include <bits/stdc++.h>
#define _ ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
using namespace std;

void solve()
{
  long long n, res; cin>>n; 
  vector<long long>d(n);
  vector<long long>comp;
  for(long long i(0); i<n; i++)
  {
    cin>>d[i];
  }
  sort(d.begin(), d.end());
  res=d[0]*d[n-1];

  for(long long i(2); i*i<=res; i++)
  {
    if(res%i==0)
    {
      comp.push_back(i);
      if(i!=res/i)
      {
        comp.push_back(res/i);
      }
    }
  }
  sort(comp.begin(), comp.end());

  if(comp==d)
  {
    cout<<res<<"\n";
  }
  else
  {
    cout<<-1<<"\n";
  }
}

int main()
{_
  long long t; cin>>t;
  for(long long i(0); i<t; ++i)
  {
    solve();
  }
}