#include<bits/stdc++.h>
using namespace std;
#define rep(i,a,b) for(int i=a;i<b;i++)



typedef long long ll;
int N, A[20];
ll dp[20][2];
//-----------------------------------------------------------------------------------
int main() {
    cin >> N;
    rep(i, 0, N) cin >> A[i];

    rep(i, 0, N) {
        dp[i][0] = -(1LL << 60);
        dp[i][1] = 1LL << 60;
    }

    dp[0][0] = dp[0][1] = A[0];
    rep(i, 1, N) rep(j, 0, 2) {
        dp[i][0] = max(dp[i][0], dp[i - 1][j] + A[i]);
        dp[i][0] = max(dp[i][0], dp[i - 1][j] - A[i]);
        dp[i][0] = max(dp[i][0], dp[i - 1][j] * A[i]);
        if(0 != A[i]) dp[i][0] = max(dp[i][0], dp[i - 1][j] / A[i]);

        dp[i][1] = min(dp[i][1], dp[i - 1][j] + A[i]);
        dp[i][1] = min(dp[i][1], dp[i - 1][j] - A[i]);
        dp[i][1] = min(dp[i][1], dp[i - 1][j] * A[i]);
        if (0 != A[i]) dp[i][1] = min(dp[i][1], dp[i - 1][j] / A[i]);
    }

    cout << dp[N - 1][0] << endl;
}