#include <bits/stdc++.h>
using namespace std;
#define int long long
int n,ans=-1e18,a[20];
void dfs(int now,int sum){
    if(now==n+1){
        ans=max(ans,sum);
        return;
    }
    dfs(now+1,sum+a[now]);
    dfs(now+1,sum*a[now]);
    dfs(now+1,sum-a[now]);
}
signed main(){
    cin>>n;
    for (int i=1;i<=n;i++){
        cin>>a[i];
    }
    dfs(2,a[1]);
    cout<<ans;
    return 0;
}