#include <bits/stdc++.h>
using namespace std;

int main() {
    int n;
    cin >> n;
    vector<int> a(n);
    for (int i = 0; i < n; i++) {
        cin >> a.at(i);
    }
    int64_t l = a.at(0), r = a.at(0);
    for (int i = 1; i < n; i++) {
        vector<int64_t> v;
        v.push_back(l + a.at(i));
        v.push_back(r + a.at(i));
        v.push_back(l - a.at(i));
        v.push_back(r - a.at(i));
        v.push_back(l * a.at(i));
        v.push_back(r * a.at(i));
        if (a.at(i)) {
            v.push_back(l / a.at(i));
            v.push_back(r / a.at(i));
        }
        l = *min_element(v.begin(), v.end());
        r = *max_element(v.begin(), v.end());
    }
    cout << r << endl;
}