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 Ruby (judge verdict: Accepted)

loop {
	n = gets.to_i
	if n == 0 then
		break
	end
	
	a = []
	n.times {
		a.push gets.to_i
	}

	m1 = -100001
	n.times { |i|
		s = 0
		m0 = -100001
		for j in i .. (n-1)
			s += a[j];
			if m0 < s then
				m0 = s
			end 
		end
		if m1 < m0 then
			m1 = m0
		end
	}
	puts m1
}