Array Max Consecutive Sum

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

Example
let inputArray = [2,3,5,1,6]; and k is 2 The output should ne arrayMaxConsecutiveSum(inputArray,k) => 8.

All possible sums of 2 consecutive elements are

• 2 + 3 = 5;
  
• 3 + 5 = 8;
  
• 5 + 1 = 6;
  
• 1 + 6 = 7;
  

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

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

The function arrayMaxConsecutiveSum takes in two arguments: inputArray which is an array of numbers, and k which is a positive integer. The function calculates the maximum sum of k consecutive elements in inputArray.

The algorithm for the function is as follows:

1. Initialize two variables, sum and max to 0. sum will keep track of the current sum of k consecutive elements, and max will keep track of the maximum sum found so far.
   
   
2. The first loop runs from 0 to k-1, and adds the first k elements of inputArray to sum. At the end of the loop, sum contains the sum of the first k elements in inputArray, and max is set to sum since this is the maximum sum found so far.
   
   
3. The second loop runs from k to the end of the inputArray. In each iteration, sum is updated by subtracting the value of the k-th element before the current k elements and adding the value of the current k-th element. The updated sum is then compared to max, and if it is greater, max is updated to sum.
   
   
4. Finally, the function returns the value of max, which is the maximum sum of k consecutive elements in inputArray.
   
   Example: arrayMaxConsecutiveSum([2,3,5,1,6],2).
   
   sum = 2 + 3 = 5
   
   max = sum = 5
   
   On the first iteration of the second loop, sum = sum - 2 + 5 = 8
   max is updated to sum = 8
   
   On the second iteration of the second loop, sum = sum - 3 + 1 = 6
   max remains 8 since 6 is not greater than 8.
   
   The function returns 8 which is the maximum sum of 2 consecutive elements in [2,3,5,1,6].