Our next problem calculates sums within a list.

Given a list of integers, return the maximum sum possible from a contiguous sub-list. A sub-list is an uninterrupted portion of the list (up to and including the entire list).

nums = [1, -7, 2, 15, -11, 2]

maximum_sub_sum(nums)
# 17
# The sum of sub-list nums[2:4]

Clarifying Questions:

• Are there constraints on time or space efficiency?
  • No! Any solution will do.
• Are all the numbers positive?
  • No! Negative numbers can be in the input.
• How big or small can the sub-list be?
  • From a single element to the entire list.