Max sum of k consecutive in Python
Python interview exercise on Lists & Comprehensions, difficulty 2 of 3. Solve it in the editor beside a worked example, or cold in Interview mode with the example hidden; the tests run the moment you do.
Write max_window_sum(nums, k) that returns the largest sum of k consecutive elements, or None when k is below 1 or larger than the list. Slide the window instead of re-adding every one.
Each exercise pairs a worked example with a twin problem to solve in a real editor; the tests run the moment you do. Interview mode hides the example: solve it from memory, without the hint or the solution, and it counts as solved cold. Progress is saved in your browser, and in your account if you sign in.