#include<stdio.h>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<utility>
#include<memory>
#include<cmath>
 
#define ALL(g) (g).begin(),(g).end()
#define REP(i, x, n) for(int i = x; i < n; i++)
#define rep(i,n) REP(i,0,n)
#define EXIST(s,e) ((s).find(e)!=(s).end())
#define pb push_back
 
using namespace std;
 
typedef long long ll;
typedef pair<int,int> P;
const int mod=1e9+7;
const int INF=1<<30;
const int MAX_N=100001;

int main(){
  int N;
  cin >> N ;
  ll ma=0,mi=0,a;
  rep(i,N){
    cin >> a ;
    ll temp=mi;
    ma=max(max(ma+a,ma*a),max(ma-a,mi*a));
    if(a)  mi=min(min(mi+a,mi-a),min(mi/a,min(mi*a,temp*a)));
  }
  cout << ma << endl;
  return 0;
}