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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

JAVA Date and time (HACKERRANK problem)

Problem The Calendar class is an abstract class that provides methods for converting between a specific instant in time and a set of calendar fields such as YEAR, MONTH, DAY_OF_MONTH, HOUR, and so on, and for manipulating the calendar fields, such as getting the date of the next week. You are given a date. Your task is to find what the  day  is on that date. Input Format A single line of input containing the space separated month, day and year, respectively, in      format. Constraints Output Format Output the correct day in capital letters. Sample Input 08 05 2015 Sample Output WEDNESDAY Explanation The day on August  th    was  WEDNESDAY . Solution: import java.io.*; import java.util.*; import java.text.*; import java.math.*; import java.util.regex.*; public class Solution {     public static void main(String[] args) {         Scanner in = new Scanner(System.in);         String