#include <iostream>

using namespace std;
int a[5000], b[5000], c[5000];

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

    b[0] = a[0];
    for(int i = 1; i < n; i++){
      b[i] = b[i-1] + a[i];
    }

    c[0] = b[0];
    for(int i = 1; i < n; i++){
      c[i] = min(c[i-1], b[i]);
    }

    int ans = 0;
    for(int i = 1; i < n; i++){
      ans = max(ans, b[i] - c[i-1]);
      ans = max(ans, b[i]);
    }
    cout << ans << endl;
  }
}