Array Max Consecutive Sum

Given array of integers, find the maximal possible sum of its k consecutive elements.

Example

For inputArray = [2, 3, 5, 1, 6] and k = 2, the output should be

array_max_consecutive_sum(inputArray, k) = 8

All possible sums of 2 consecutive elements are:

• 2 + 3 = 5;
• 3 + 5 = 8;
• 5 + 1 = 6;
• 1 + 6 = 7. Thus, the answer is 8.

Input/Output

• [input] array.integer inputArray

  Array of positive integers.

  Guaranteed constraints:3 ≤ inputArray.length ≤ 105, 1 ≤ inputArray[i] ≤ 1000.

• [input] integer k

  An integer (not greater than the length of inputArray).

Solution

PYTHON

def array_max_consecutive_sum(input_list, k):
    max_sum = current_sum = sum(input_list[:k])

    for i in range(len(input_list) - k):
        current_sum += input_list[i + k] - input_list[i]
        max_sum = max(max_sum, current_sum)
    return max_sum


print(array_max_consecutive_sum([2, 3, 5, 1, 6], 2))

JAVASCRIPT

function arrayMaxConsecutiveSum(inputArray, k) {
  let max = 0;
  for (let i = 0; i < inputArray.length - k + 1; i++) {
    let sum = 0;
    for (let j = i; j < i + k; j++) {
      sum += inputArray[j];
    }
    if (sum > max) {
      max = sum;
    }
  }
  return max;
}

console.log(arrayMaxConsecutiveSum([2, 3, 5, 1, 6], 2));