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: Time Limit Exceeded)

answers = []

while n = gets.to_i
  break if n == 0
  data = []
  n.times { data << gets.to_i }

  answer = -1.0 / 0

  i = 0
  while i < data.size
    j = 0
    while j < data.size
      answer = [data.slice(i, j + 1).inject(0) { |a, e| a + e }, answer].max
      j += 1
    end
    i += 1
  end
  answers << answer
end

answers.each { |answer| puts answer }