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: Wrong Answer)

#include<stdio.h>
int max(int a, int b) {
  if (a >= b) return a;
  else return b;
}
int main() {
  int i, j, N, n, k;
  int sum[5000];
  while (1) {
    n = 0;
    scanf("%d", &N);
    if(!N) break;
    for (i = 0; i < N; i ++) scanf("%d", &sum[i]);
    for (i = 0; i < N; i ++) {
      k = 0;
      for (j = i; j < N; j ++) {
	k += sum[j];
	n = max(n, k);
      }
    }
    printf("%d\n", n);
  }
  return 0;
}