#include <bits/stdc++.h>
using namespace std;
#define int long long
int n,a[20],dp[20][2];
signed main(){

    cin>>n;
    for (int i=1;i<=n;i++){
        cin>>a[i];
    }
    dp[1][0]=dp[1][1]=a[1];
    for (int i=2;i<=n;i++){
        dp[i][0]=max(max(dp[i-1][0]+a[i],dp[i-1][0]-a[i]),max(dp[i-1][1]*a[i],dp[i-1][0]*a[i]));
        dp[i][1]=min(min(dp[i-1][1]+a[i],dp[i-1][1]-a[i]),min(dp[i-1][1]*a[i],dp[i-1][0]*a[i]));
        if(a[i]!=0){
            int val1=max(dp[i-1][0]/a[i],dp[i-1][1]/a[i]),val2=min(dp[i-1][0]/a[i],dp[i-1][1]/a[i]);
            dp[i][0]=max(dp[i][0],val1);
            dp[i][1]=min(dp[i][1],val2);
        }
    }
    cout<<dp[n][0];
    return 0;
}