Problem:
Maximum Sum Sequence

Given a sequence of numbers a1, a2, a3, ..., an, find the maximum sum of a contiguous subsequence of those numbers. Note that, a subsequence of one element is also a contiquous subsequence.

Input

The input consists of multiple datasets. Each data set consists of:

n
a1
a2
.
.
an

You can assume that 1 ≤ n ≤ 5000 and -100000 ≤ ai ≤ 100000.

The input end with a line consisting of a single 0.

Output

For each dataset, print the maximum sum in a line.

Sample Input

7
-5
-1
6
4
9
-6
-7
13
1
2
3
2
-2
-1
1
2
3
2
1
-2
1
3
1000
-200
201
0

Output for the Sample Input

19
14
1001

Solution in C# (judge verdict: Accepted)

using System;

public class C
{
    public const int INF = -999999999;
}

public class Hello
{
    public static void Main()
    {
        while (true)
        {
            var n = int.Parse(Console.ReadLine().Trim());
            if (n == 0) break;
            var dp0 = 0;
            var ret = C.INF;
            for (int i = 1; i <= n; i++)
            {
                var a = int.Parse(Console.ReadLine().Trim());
                var dp1 = Math.Max(dp0 + a, a);
                ret = Math.Max(ret, dp1);
                dp0 = dp1;
            }
            Console.WriteLine(ret);
        }
    }
}