#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <stack>
#include <queue>
#include <list>
#include <set>
#include <map>
#include <numeric>
#include <regex>
#include <tuple>
#include<iomanip>
using namespace std;

typedef long long ll;
typedef pair<int, int> P;
#define MOD 1000000007 // 10^9 + 7
#define INF 1000000000 // 10^9
#define LLINF 1LL<<60

ll f(ll x, ll y, int ope) {
	if (ope == 0) return x + y;
	else if (ope == 1) return x - y;
	else if (ope == 2) return x*y;
	else return x / y;
}

int a[16];

int main() {
	cin.tie(0);
	ios::sync_with_stdio(false);

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

	ll up = a[0];
	ll bottom = a[0];

	for (int i = 1; i < N; i++) {
		ll tmpup = -LLINF;
		ll tmpbottom = LLINF;

		for (int j = 0; j < 3; j++) {
			tmpup = max(tmpup, f(up, a[i], j));
			tmpup = max(tmpup, f(bottom, a[i], j));
			tmpbottom = min(tmpbottom, f(up, a[i], j));
			tmpbottom = min(tmpbottom, f(bottom, a[i], j));

		}
		if (a[i] != 0) {
			tmpup = max(tmpup, f(up, a[i], 3));
			tmpup = max(tmpup, f(bottom, a[i], 3));
			tmpbottom = min(tmpbottom, f(up, a[i], 3));
			tmpbottom = min(tmpbottom, f(bottom, a[i], 3));
		}
		up = tmpup;
		bottom = tmpbottom;
	}

	cout << up << endl;

	return 0;
}