#include <iostream>
#include <vector>
#include <string>

using namespace std;

char op[] = {'*', '/', '+', '-'};

int main(){
    int N; cin >> N;
    vector<int> A(N);
    for(int i=0;i<N;i++) cin >> A[i];

    int tot_max = A[0];
    int tot_min = A[0];

    for(int i=1;i<N;i++){
        int next_max = -2e9;
        int next_min = 2e9;
        for(auto cur : {tot_max, tot_min}){
            for(int j=0;j<4;j++){
                int next;
                if(op[j] == '/' && A[i]==0) continue;
                switch(op[j]){
                    case '+' : next = cur + A[i]; break;
                    case '-' : next = cur - A[i]; break;
                    case '*' : next = cur * A[i]; break;
                    case '/' : next = cur / A[i]; break;
                }
                next_max = max(next_max, next);
                next_min = min(next_min, next);
            }
        }
        tot_max = next_max;
        tot_min = next_min;
    }
    cout << tot_max << endl;
    return 0;
}