Maximum Subarray (LeetCode #53)

Challenge Statement

• 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.
• This challenge corresponds to LeetCode #53.

Constraints

• 1 <= nums.length <= 105
• -104 <= nums[i] <= 104

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

Solution

Below is my solution and some test cases. This solution has a linear time complexity O(n) and a constant space complexity O(1), where n is the length of the input list.