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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...
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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...
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Diagonal Traversal of Matrix in Javascript

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Diagonal Traversal of Matrix/2D Array in Javascript Problem statement:   In this post, we will traverse a given matrix/2D array diagonally (from center to top right corner). Refer below attached diagram for better understanding. Diagonal pattern: Expected Output: expected   output :     1     6     11     16     2     7     12     3     8     4 Input Matrix:  let   input2DArray  = [   [ 1 ,  2 ,  3 ,  4 ],   [ 5 ,  6 ,  7 ,  8 ],   [ 9 ,  10 ,  11 ,  12 ],   [ 13 ,  14 ,  15 ,  16 ], ]; Solution Approach :  When we think about the pattern required, we can confirm that there will always be n number of diagonals that we will be traversing, that means the outer loop will be from 0 to n-1.  I have added be...
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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 =...
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LeetCode Problem: "Reverse Integer"

  LeetCode  Problem and solution in Javascript     Objective:   In this challenge, we will solve the “ Reverse Integer ” LeetCode   puzzle using  javascript .   Problem statement:   Given a 32-bit signed integer, reverse digits of an integer. It must return the display text as shown in the examples:   Example 1: Input: 123 Output: 321 Example 2: Input: -123 Output: -321 Example 3: Input: 120 Output: 21 Note: Assume we are dealing with an environment which could only store integers within the 32-bit signed integer range: [−2 31 ,  2 31  − 1]. For the purpose of this problem, assume that your function returns 0 when the reversed integer overflows.   Solution  :   var reverse = function(input) {                  if(Math.sign(input)==1){             var result = parseInt(input.toString().split('').reverse().join(''))     ...
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