Given an array of positive numbers and a positive number ‘k’, find the maximum sum of any contiguous subarray of size ‘k’.

max_sub_array_of_size_k.py

# By Drem
def max_sub_array_of_size_k(k, arr):
  maximumSum = 0
  currentMaximumSum = 0
  subArrayStart = 0

  for subArrayEnd in range(len(arr)):
    maximumSum += arr[subArrayEnd]
    if subArrayEnd >= k - 1:
      if maximumSum > currentMaximumSum:
        currentMaximumSum = maximumSum
      maximumSum -= arr[subArrayStart]
      subArrayStart+=1
  
  return currentMaximumSum


def main():
  print("Maximum sum of a subarray of size K: " + str(max_sub_array_of_size_k(3, [2, 1, 5, 1, 3, 2])))
  print("Maximum sum of a subarray of size K: " + str(max_sub_array_of_size_k(2, [2, 3, 4, 1, 5])))


main()