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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Javascript Codewars Problem: "Who likes it?"

 Codewars Problem and solution in Javascript

 
 

Objective: 

In this challenge, we will solve the “Who likes it?” Codewars puzzle using javascript. 

Problem statement: 

You probably know the "like" system from Facebook and other pages. People can "like" blog posts, pictures or other items. We want to create the text that should be displayed next to such an item.


Implement a function likes :: [String] -> String, which must take in input array, containing the names of people who like an item. It must return the display text as shown in the examples: 


Examples: 

Input : []

Output : no one likes this


Input : ['Peter']  

Output:  Peter likes this


Input : ['Jacob', 'Alex'] 

Output : Jacob and Alex like this


Input : ['Max', 'John', 'Mark']

Output : Max, John and Mark like this


Input : ['Alex', 'Jacob', 'Mark', 'Max']     

Output : Alex, Jacob and 2 others like this


Solution Hint: 

we will create conditions based on the length of names, and return strings accordingly.

  

  

Solution : 


function likes(names) {

  // code starts here

  //console.log("input "+names[0]+" : "+names.length)

  if(names.length == 0)

    return 'no one likes this';

  else if(names.length == 1)

    return names[0]+' likes this' ;

  else if(names.length == 2)

    return names[0]+' and '+names[1]+' like this' ;

  else if(names.length == 3)

    return names[0]+', '+names[1]+' and '+names[2]+' like this' ;

  else if (names.length > 3)

    return names[0]+', '+names[1]+' and '+ (names.length-2)+' others like this' ;

}

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