#53. Maximum Subarray

https://leetcode.com/problems/maximum-subarray/#/description

Paste_Image.png

说明

• 查找连续子数组，使之sum最大

思路

• 初始化maxSum = a[0], curSum = a[0]
• 如果 curSum > 0 则curSum = curSum + a[i]
• 如果 curSum < 0 则 curSum = a[i]
• maxSum = max(maxSum, curSum)

# Time O(n)
# Space O(1)
class Solution(object):
    def maxSubArray(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        curSum = nums[0]
        maxSum = nums[0]
        for i in range(1, len(nums)):
            if curSum >= 0:
                curSum = curSum + nums[i]
            else:
                curSum = nums[i]
            maxSum = max(maxSum, curSum)
        return maxSum