#include<cstdio>
#include <iostream>
#include<algorithm>
#include<string>
#include<queue>
#include<vector>
#include<functional>
#include<cmath>
#include<map>
#include<stack>
#include<set>
using namespace std;
typedef long long ll;
typedef pair<int, int> P;

int a[17];

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

	int ans = a[0];
	for (int i = 0; i < N; i++) {
		if (ans >= 0) {
			if (a[i] != 0 && ans != 0 && a[i + 1] != 0 && a[i + 1] != 1 && a[i + 1] > 0) 
				ans *= a[i + 1];
			else if (a[i + 1] == 1 || (ans ==0&&  a[i] != 0 && a[i+1] > 0)) 
				ans += a[i + 1];
			else if (a[i+1] < 0 || (ans == 0 &&a[i] != 0 && a[i + 1] < 0)) 
				ans -= a[i + 1];
			else if(a[i+1] != 0 && ans != 0 && a[i] != 0)
				ans *= a[i + 1];
		}
		else {
			if (a[i + 1] > 0 || a[i+1] == 0) {
				ans += a[i + 1];
			}
			else if(a[i+1] < 0 && a[i+1] != -1){
				ans *= a[i + 1];
			}
			else if (a[i+1] == -1) {
				ans -= a[i + 1];
			}
		}
	}
	cout << ans << endl;
	return	0;
}