题目
Given an integer array nums, find the contiguous subarray (containing at least one number) which has the largest sum and return its sum.
A subarray is a contiguous part of an array.
Example 1:
Input: nums = [-2,1,-3,4,-1,2,1,-5,4]
Output: 6
Explanation: [4,-1,2,1] has the largest sum = 6.
Example 2:
Input: nums = [1]
Output: 1
Example 3:
Input: nums = [5,4,-1,7,8]
Output: 23
Constraints:
1 <= nums.length <= 105-104 <= nums[i] <= 104
Follow up: If you have figured out the O(n) solution, try coding another solution using the divide and conquer approach, which is more subtle.
思路
贪婪算法
进阶：归并算法，待实现
代码
python版本：
class Solution:
def maxSubArray(self, nums: List[int]) -> int:
maxn, res = 0, -math.inf
for num in nums:
maxn += num
res = max(res, maxn)
if maxn < 0:
maxn = 0
return res
