#include <iostream>
#include <vector>
using namespace std;

int main()
{
    int n;
    cin>>n;

    vector <int> m(n);
    int min_el=0;

    int max_sum=0;

    cin>>m[0];
    max_sum=m[0];

    if (min_el>m[0]) min_el=m[0];

    for(int i=1; i<n; i++)
    {
        cin>>m[i];
        m[i]+=m[i-1];
        if (max_sum<m[i]-min_el) max_sum=m[i]-min_el;

        if (min_el>m[i]) min_el=m[i];
    }

    cout << max_sum << endl;
    return 0;
}