49 leetcode - Maximum Subarray

#!/usr/bin/python
# -*- coding: utf-8 -*-
'''
Maximum Subarray
Find the contiguous subarray within an array (containing at least one number) which has the largest sum.
For example, given the array [-2,1,-3,4,-1,2,1,-5,4],
the contiguous subarray [4,-1,2,1] has the largest sum = 6.
'''
class Solution(object):
def maxSubArray(self, nums):
"""
:type nums: List[int]
:rtype: int
"""
length = len(nums)
if length == 0:
return 0

if length == 1:
return nums[0]

sum = max_sum = nums[0]

for val in nums[1:]:
sum = val if sum < 0 else sum + val
if sum > max_sum:
max_sum = sum

return max_sum
if __name__ == "__main__":
s = Solution()
print s.maxSubArray([-2,1,-3,4,-1,2,1,-5,4])