Window Sliding Technique in JavaScript

window_sliding_in_javascript.js

// This gist is for my YouTube video which I tried to explain Window Sliding Technique.
// You can watch it from here: https://youtu.be/ZlnZkfEcbxs
//
// Given an array of integers of size ‘n’. Calculate the maximum sum possible
// for ‘k’ consecutive elements in the array.
//
// Input  : [10, 20, 30, 40, 50, 60, 70]
//
//          k = 3
// Output : 180

const arr = [10, 20, 30, 40, 50, 60, 70];
const k = 3;

function maxSum(arr, k) {
  if (k > arr.length) {
    return "invalid";
  }

  let windowTotal = 0;
  for (let i = 0; i < k; i++) {
    windowTotal += arr[i];
  }

  //   const arr = [10, 20, 30, 40, 50, 60, 70];
  //   const k = 3;

  let maxSumResult = windowTotal;
  for (let i = k; i < arr.length; i++) {
    windowTotal += arr[i] - arr[i - k];
    maxSumResult = Math.max(windowTotal, maxSumResult);
  }

  return maxSumResult;
}

console.log(maxSum(arr, k));

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