#include <bits/stdc++.h>
using namespace std;
#define FOR(i, n) for(int i = 0; i < (n); i++)
#define MEM(a, x) memset(a, x, sizeof(a))
#define ALL(a) a.begin(), a.end()
#define UNIQUE(a) a.erase(unique(ALL(a)), a.end())
typedef long long ll;
typedef pair<int, int> P;

int n;
ll dp[20][2];

int main(int argc, char const *argv[]) {
	ios_base::sync_with_stdio(false);
	cin >> n;
	FOR(i, n) {
		ll a;
		cin >> a;
		dp[i+1][0] = max({dp[i][0]+a, dp[i][0]-a, dp[i][0]*a, dp[i][1]+a, dp[i][1]-a, dp[i][1]*a});
		dp[i+1][1] = min({dp[i][0]+a, dp[i][0]-a, dp[i][0]*a, dp[i][1]+a, dp[i][1]-a, dp[i][1]*a});
	}
	cout << dp[n][0] << endl;
	return 0;
}