#include "bits/stdc++.h"
#define REP(i,n,N) for(ll i=(n); i<(N); i++)
#define RREP(i,n,N) for(ll i=(N-1); i>=n; i--)
#define CK(n,a,b) ((a)<=(n)&&(n)<(b))
#define ALL(v) (v).begin(),(v).end()
#define p(s) cout<<(s)<<endl
#define p2(a,b) cout<<(a)<<" "<<(b)<<endl
#define v2(T) vector<vector<T>>
typedef long long ll;
using namespace std;
const ll inf= 1e18;


ll dp[20],dp2[20];
ll a[20];
int main(){
    int N;
    cin>>N;
    REP(i,0,N) cin>>a[i];
    REP(i,0,N) {
        dp[i]=-inf;
        dp2[i]=inf;
    }
    dp[0]=dp2[0]=a[0];
    REP(i,1,N) {
        dp[i] = max({dp[i], dp[i - 1] * a[i], dp[i - 1] + a[i], dp[i - 1] - a[i]});
        dp[i] = max({dp[i], dp2[i - 1] * a[i], dp2[i - 1] + a[i], dp2[i - 1] - a[i]});
        dp2[i] = min({dp2[i], dp[i - 1] * a[i], dp[i - 1] + a[i], dp[i - 1] - a[i]});
        dp2[i] = min({dp2[i], dp2[i - 1] * a[i], dp2[i - 1] + a[i], dp2[i - 1] - a[i]});
        if(a[i]!=0){
            dp[i] = max({dp[i], dp[i-1] / a[i], dp2[i-1] / a[i]});
            dp2[i] = min({dp2[i], dp[i-1] / a[i], dp2[i-1] / a[i]});
        }
    }
    p(max(dp[N-1],dp2[N-1]));
    return 0;
}