一、45. 跳跃游戏 II

代码：

class Solution:
    def jump(self, nums: List[int]) -> int:
        start = step = 0
        end = 1
        n = len(nums)
        while end < n:
            max_num = 0
            for i in range(start,end):
                max_num = max(max_num, i+nums[i])
            start,end,step = end,max_num + 1,step+1
        return step

二、 53. 最大子数组和

代码：

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