#include <cstdio>
#include <cstring>
#include <algorithm>
#define ll long long
using namespace std;
int const MAX = 1e3 + 5;
ll dp[MAX];
int val[MAX];

int main()
{
    int n;
    while(scanf("%d", &n) != EOF && n)
    {
        ll ans = 0;
        for(int i = 0; i < n; i++)
        {
            scanf("%d", &val[i]);
            dp[i] = val[i];
        }
        for(int i = 0; i < n; i++)
            for(int j = 0; j <= i; j++)
                if(val[i] > val[j])
                    dp[i] = max(dp[i], dp[j] + val[i]);
        for(int i = 0; i < n; i++)
            ans = max(ans, dp[i]);
        printf("%lld\n", ans);
    }
}