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: Time Limit Exceeded)

main(){int i,n,m,p[5001],j,k,l;
	while(scanf("%d",&k)){
		for(i=0;i<5001;i++)p[i]=0;
		if(!k)break;n=0;i=k;
		while(i-->0)scanf("%d",&p[i]);
		while(i++<k){
			for(j=0;j++<k;){
				m=0;
				for(l=i;l++<j;){
					m+=p[l];
				}
				if(n<m)n=m;
			}
		}
		printf("%d\n",n);
	}
}