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53. Maximum Subarray

53. Maximum Subarray

Easy


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.


 class Solution:
    def maxSubArray(self, nums: List[int]) -> int:
        current_sum = max_sum = nums[0]
        for num in nums[1:]:
            current_sum = max(num, current_sum+num)
            max_sum = max(max_sum, current_sum)

        return max_sum

(k := next(iter(d)), d.pop(k)) will remove the leftmost (first) item (if it exists) from a dict object. And if you want to remove the right most/recent value from the dict

d.popitem()
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