#include <algorithm>
#include <cstdio>
#include <iostream>
#include <map>
#include <cmath>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <vector>
#include <stdlib.h>
#include <stdio.h>
#include <bitset>
using namespace std;
#define FOR(I,A,B) for(int I = (A); I < (B); ++I)
vector<map<long long, bool> > vm(16);
int main(){
  int n;
  cin >> n;
  int a[n];
  FOR(i,0,n){
    cin >> a[i];
  }
  vm[0][a[0]] = true;
  FOR(i,1,n){
    for (auto itr = vm[i-1].begin(); itr != vm[i-1].end(); ++itr){
      vm[i][itr->first + a[i]] = true;
      vm[i][itr->first - a[i]] = true;
      vm[i][(long long)(itr->first * a[i])] = true;
      if(a[i] != 0){
        vm[i][(long long)(itr->first / a[i])] = true;
      }
    }
  }
  auto itr = vm[n-1].end();
  itr--;
  cout << itr->first << endl;
  return 0;
}