/*
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*/
#include<bits/stdc++.h>
using namespace std;
#define int long long
//#define eps 1e-9
//#define ENF 1e13
const int N=1e4;
const int mod=1e9+7;
inline int read()
{
   int x=0,f=1;char ch=getchar();
   while (ch<'0'||ch>'9'){if (ch=='-') f=-1;ch=getchar();}
   while (ch>='0'&&ch<='9'){x=(x<<3)+(x<<1)+ch-48;ch=getchar();}
   return x*f;
}
void write(int x)
{
   if(x<0)putchar('-'),x=-x;
   if(x<10)putchar(x+'0');
   else write(x/10),putchar(x%10+'0');
}
int n;
int a[N];
int ans=LONG_LONG_MIN;
void dfs(int u,int sum){
	if(u==n+1){
		ans=max(ans,sum);
		return;
	}
	dfs(u+1,sum+a[u]);
	dfs(u+1,sum-a[u]);
	dfs(u+1,sum*a[u]);
//	dfs(u+1,sum/a[u]);
	return;
}
signed main(){
//	freopen("operations.in","r",stdin);
//	freopen("operations.out","w",stdout);
	n=read();
	int Q=0;
	for(int i=1;i<=n;i++)a[i]=read(),Q+=(a[i]<0);
	if(a[1]<0&&Q==1){
		int sum=a[1];
		for(int i=2;i<=n;i++){
			if(a[i]==0){
dfs(i+1,0);
cout<<ans<<"\n";
return 0;
                       }
			if(sum+a[i]<sum/a[i])sum/=a[i];
			else sum+=a[i];
			if(sum>=0){
				dfs(i+1,sum);
				cout<<ans<<"\n";
				return 0;
			}
		}
		cout<<sum<<"\n";
		return 0;
	}
	dfs(2,a[1]);
	
	cout<<ans<<"\n";
   return 0;
}
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