#include <bits/stdc++.h>
using namespace std;
#define repl(i,a,b) for(int i=(int)(a);i<(int)(b);i++)
#define rep(i,n) repl(i,0,n)
#define mp(a,b) make_pair((a),(b))
#define pb(a) push_back((a))
#define all(x) (x).begin(),(x).end()
#define uniq(x) sort(all(x)),(x).erase(unique(all(x)),end(x))
#define fi first
#define se second
#define dbg(x) cout<<#x" = "<<((x))<<endl
template<class T,class U> ostream& operator<<(ostream& o, const pair<T,U> &p){o<<"("<<p.fi<<","<<p.se<<")";return o;}
template<class T> ostream& operator<<(ostream& o, const vector<T> &v){o<<"[";for(T t:v){o<<t<<",";}o<<"]";return o;}

#define INF 2147483600123456789

int main(){
  int n;
  cin>>n;
  vector<int> vec(n);
  rep(i,n) cin>>vec[i];

  vector<vector<long>> dp(n,vector<long>(2));

  dp[0][0] = dp[0][1] = vec[0];

  rep(i,n-1){
    dp[i+1][0] = -INF;
    dp[i+1][1] = INF;
    rep(j,2){
      long a = dp[i][j]+vec[i+1];
      long b = dp[i][j]-vec[i+1];
      long c = dp[i][j]*vec[i+1];
      long d = (vec[i+1]==0)?(dp[i][j]):(dp[i][j]/vec[i+1]);
      dp[i+1][0] = max(dp[i+1][0], max(max(a,b), max(c,d)));
      dp[i+1][1] = min(dp[i+1][1], min(min(a,b), min(c,d)));
    }
  }

  cout << dp[n-1][0] << endl;

  return 0;
}