leetcode-python-最大子序和▲

逐个求，保存最大和。

如果前序和小于0则舍弃，始终以正值优先。

class Solution:
    def maxSubArray(self, nums: List[int]) -> int:
        cur = nums[0]
        maximum = nums[0] 
        for i in range(1,len(nums)):
            cur = max(cur,0) + nums[i]
            maximum = max(maximum,cur)
        return maximum