Max sum of k consecutive in C#
C# interview exercise on Collections & LINQ, 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 MaxWindowSum(nums, k) that returns the largest sum of k consecutive elements, or null 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.