Algorithms Challenge - #2: Sliding Window

programming
1

Create a function that finds the maximum sum of any subarray of fixed size k in a given array of integers. Return -1 if k is invalid (k <= 0 or k > length of the array).

Examples:

  • max_subarray_sum_of_size_k([1,4,2,10,23,3,1,0,20], 4) returns 29 (subarray [4,2,10,23)
  • max_subarray_sum_of_size_k([-2, -3, -1, -4], 2) returns -3
def max_subarray_sum_of_size_k(arr, k):
    """One-line docstring placeholder"""
    pass

Rules:

  • Any language or pseudocode is fine. The stub just shows the shape.
  • Say the time complexity of your approach.
  • short rule
  • O(n) time, O(1) extra space
  • works for negative numbers
  • edge case handling for invalid k

Post your solution as a reply. Answer goes up in about a day.