#include <iostream>
#include <cstdio>
#include <vector>
#include <algorithm>
#include <cmath>
#include <utility>

#define ll (long long)
#define REP(i,n) for(int i = 0;i<(int)n;i++)
#define FOR(i,a,b) for(int i = (a);i < (b);i++)
#define RFOR(i,a,b) for(int i = (a);i>(b);i--)


using namespace std;

int main (void){
  
    int number;
    int max;
    int answer[5010] = {0};
    int l = 0;
    while(cin >> number,number)
    {
        int a[5010] = {0};
        vector<int>tempmax(5010,0);
        vector<int>tempmax2(5010,0);
        REP(i,number)
        cin >> a[i];
        for(int i = number;i>=0;i--)
            for(int j = 0; j<i;j++)
            {
                tempmax[i] +=a[j];
            }
        for(int k = 0;k<number;k++)
            for(int m = k;m<number;m++)
            {
                if(k == m)
                    tempmax2[k] = a[k];
                else if(tempmax2[k]+a[m] >= tempmax2[k])
                    tempmax2[k]+= a[m];
                else
                    break;
            }
        sort(tempmax.begin(),tempmax.end(),greater<int>());
        sort(tempmax2.begin(),tempmax2.end(),greater<int>());
        if(tempmax[0]>tempmax2[0])
            answer[l] = tempmax[0];
        else
            answer[l] = tempmax2[0];
        printf("%d\n",answer[l]);
        l++;
    }
    return 0;
}