new_contents: """
  Given an integer array nums, find the contiguous subarray (containing at least one number) which has the largest sum and return its sum.
  
  Example:
  
  Input: [-2,1,-3,4,-1,2,1,-5,4],
  Output: 6
  Explanation: [4,-1,2,1] has the largest sum = 6.
  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:
          if len(nums) == 0:
              return 0
          total, running = nums[0], nums[0]
          for n in nums[1:]:
              running += n
              if n > running:
                  running = n
              if running > total:
                  total = running
          return total
  
subject: Add day 3