#include<bits/stdc++.h>


using namespace std;  
#define FOR(i,a,b) for(int i=(a);i<(b);i++)
#define REP(i,n) for(int i=0;i<(n);i++)  
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
#define pii pair<int,int>
#define piii pair<int,pii>
#define mp make_pair
#define pb push_back  
#define ALL(a) (a).begin(),(a).end()
#define FST first
#define SEC second  
const int INF = (INT_MAX/2);
const double eps = 1e-14;
const double PI = M_PI;  
#define DEB cout<<"!"<<endl
#define SHOW(a,b) cout<<(a)<<" "<<(b)<<endl  
#define DIV 1000000007

int main(){
	int N; cin >> N;
	 
	ll now_max,now_min;
	
	
	REP(i,N){
		ll a; cin >> a;
		if(i==0){
			now_max = a;
			now_min = a;
		}else{
			ll t_now_max = max({now_max+a,now_max-a,a==0?(0):(now_max/a),now_max*a,now_min*a,a==0?(0):(now_min/a)});
			now_min = min({now_min-a,now_min+a,now_min*a,a==0?(now_min):now_min/a,now_max*a,now_max+a,now_max-a});
			now_max = t_now_max;
		}
	}
	cout << now_max << endl;
	
	return 0;
}