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Dutch national flag problem in Javascript

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Dutch national flag problem and solution in Javascript Problem statement:   The Dutch national flag (DNF) problem is one of the most popular programming problems proposed by Edsger Dijkstra. The flag of the Netherlands consists of three colors: white, red, and blue. The task is to randomly arrange balls of white, red, and blue such that balls of the same color are placed together. Now, let's consider an array with 3 distinct values say 0, 1 and 2. We won't be using any sort method and we need to sort this array in 0(n). Input Array :  let   arr  = [ 0 ,  2 ,  1 ,  0 ,  1 ,  2 ,  0 ,  2 ]; Expected Output: [ 0, 0, 0, 1, 1, 2, 2, 2 ] Solution Approach : When we see expected output, we can clearly see that sorted array is divided into 3 sections having values 0 , 1 and 2. So, let's divide the array in 3 sections: a) from 0th index to left boundary b) from left boundary to right boundary c) from right boundary to last index. Now we will create 2 pointers : left (starting from 0
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LeetCode Problem: "Longest Substring Without Repeating Characters"

  LeetCode  Problem and solution in Javascript     Objective:   In this challenge, we will solve the “ Longest Substring Without Repeating Characters ”  LeetCode   puzzle using  javascript .   Problem statement:   Given a string  s , find the length of the  longest substring  without repeating characters . It must return the display text as shown in the examples:   Example 1: Input: s = "abcabcbb" Output: 3 Explanation: The answer is "abc", with the length of 3. Example 2: Input: s = "bbbbb" Output: 1 Explanation: The answer is "b", with the length of 1. Example 3: Input: s = "pwwkew" Output: 3 Explanation: The answer is "wke", with the length of 3. Notice that the answer must be a substring, "pwke" is a subsequence and not a substring. Note: 0 <= s.length <= 5 * 10 4 s  consists of English letters, digits, symbols and spaces.   Solution Approach 1 : Brute Force: var lengthOfLongestSubstring = function
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HackerRank Problem: "Sherlock and Squares" in Javascript

   HackerRank  Problem and solution in Javascript     Objective:   In this challenge, we will solve the “ Sherlock and Squares ”    HackerRank   puzzle using  javascript .   Problem statement:   Watson likes to challenge Sherlock's math ability. He will provide a starting and ending value describing a range of integers. Sherlock must determine the number of  square integers  within that range, inclusive of the endpoints. Note : A square integer is an integer which is the square of an integer, e.g.  . For example, the range is   and  , inclusive. There are three square integers in the range:   and  . Function Description: Complete the squares function in the editor below. It should return an integer representing the number of square integers in the inclusive range from  to . squares has the following parameter(s): a: an integer, the lower range boundary b: an integer, the uppere range boundary Input Format The first line contains  , the number of test cases. Each of the next   lines
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