Coding Interview Prep: Sliding Window Algorithm in JavaScript

Introduction

Sliding Window Technique is a method used to efficiently solve problems that involve defining a window or range in the input data (arrays or strings) and then moving that window across the data to perform some operation within the window. This technique is commonly used in algorithms like finding subarrays with a specific sum, finding the longest substring with unique characters, or solving problems that require a fixed-size window to process elements efficiently.

Prompt

Find the maximum sum of all subarrays of size K.

Given an array of integers of size ’n’, Our aim is to calculate the maximum sum of ‘k’ consecutive elements in the array.

Solution

Solution 1: Brute Force method

So, let’s analyze the problem with Brute Force Approach. We start with the first index and sum till the kth element. We do it for all possible consecutive blocks or groups of k elements. This method requires a nested for loop, the outer for loop starts with the starting element of the block of k elements, and the inner or the nested loop will add up till the kth element.

function maxSum(arr, n, k) {
   let maxSum = 0;

    for (let i=0…