#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
using namespace std;

int main()
{
	int n; cin >> n;
	vector<int>num(n);
	for (int i = 0; i < n; i++) {
		cin >> num[i];
	}

	int ans = num[0];
	pair<int, int>maxmin(num[0], num[0]);
	for (int i = 1; i < n; i++) {
		pair<int, int>tmp = maxmin;
		maxmin.first = max(maxmin.first, tmp.first + num[i]);
		maxmin.first = max(maxmin.first, tmp.first - num[i]);
		maxmin.first = max(maxmin.first, tmp.first * num[i]);
		maxmin.first = max(maxmin.first, tmp.second * num[i]);
		maxmin.first = max(maxmin.first, tmp.second / num[i]);

		maxmin.second = min(maxmin.second, tmp.second + num[i]);
		maxmin.second = min(maxmin.second, tmp.second - num[i]);
		maxmin.second = min(maxmin.second, tmp.second * num[i]);
		maxmin.second = min(maxmin.second, tmp.first * num[i]);
		maxmin.second = max(maxmin.second, tmp.first / num[i]);
	}
	cout << maxmin.first << endl;
	return 0;
}