#include<bits/stdc++.h>
using namespace std;
#ifdef LOCAL_DEBUG
  #include "LOCAL_DEBUG.hpp"
#endif
#define int long long
const int INF = 1LL << 60;

signed main(){

  int n; cin >> n;
  vector<int> a(n);
  for(int i = 0; i < n; i++){
    cin >> a[i];
  }

  static int dp[100];
  for(int i = 0; i < n; i++){
    dp[i+1] = max(dp[i+1], dp[i] + a[i]);
    dp[i+1] = max(dp[i+1], dp[i] - a[i]);
    dp[i+1] = max(dp[i+1], dp[i] * a[i]);
  }
  cout << dp[n] << endl;

  return 0;
}