#include <iostream>
#include<algorithm>
using namespace std;
using ll = long long;
const int N = 3e5;
ll a[N];
int main()
{
    int n; cin >> n;
    ll ans = -1e7;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
        a[i] += a[i - 1];
    }
    for (int i = 1; i <= n; i++)
    {
        for (int len = n; len >= i; len--)
        {
            ans = max(ans, a[len] - a[i]);
       }
    }
    cout << ans;
    return 0;
}