#include<iostream>
#include<cmath>
#include<climits>
#include<algorithm>
using namespace std;
long long c[1000010]={0}, n,f, k, i, b[1000010] = {0}, a[1000010] = {0};
int main()
{
	cin >> n;
	for (i = 1; i <= n; i++)
	{
		cin >> b[i];
		b[i] = b[i] + b[i - 1];
	}
	f = LLONG_MIN;
	for (int j = 1; j <=n; j++)
	{
		c[j] = LLONG_MIN;
		for (int i = 0; i <= n; i++)
		{
			a[i] = b[i + j] - b[i];
			c[j] = max(c[j], a[i]);
		}
		f = max(f, c[j]);
	}
	cout << f << endl;
	return 0;
}