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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Descending Order || CodeWars Problem and solution in javascript.

 

Problem: Descending Order

Description: Your task is to make a function that can take any non-negative integer as a argument and return it with its digits in descending order. Essentially, rearrange the digits to create the highest possible number.

Examples:

Input: 42145 Output: 54421

Input: 145263 Output: 654321

Input: 123456789 Output: 987654321

 

 

Solution 1#

function descendingOrder(n){

 

  var stringNumber = n.toString();

  var arr = stringNumber.split('');

  var result = arr.sort(function(a, b){return b - a});

  var stringresult = result.join();

  stringresult= stringresult.replace(/,/g,"");

  return parseInt(stringresult)

}

 

Solution 2# (slightly more concise)

function descendingOrder(n){

  return parseInt(String(n).split('').sort().reverse().join(''))

}

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