Algorithm/HashMapSortByValueInDescending.java at master · TechRaY/Algorithm · GitHub

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import java.io.*;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import java.util.*;


public class HashMapSortByValueInDescending
{

    public static void main(String[] args)
    {
       Scanner sc=new Scanner(System.in);

        int n=sc.nextInt();
        int k,l,i=1;


        Map<Integer, Integer> lMap = new HashMap<Integer, Integer>();


       while(n-->0)
       {
           k=sc.nextInt();
           l=sc.nextInt();
           lMap.put(k,l);
       }

       Set<Entry<Integer, Integer>> entrySet = lMap.entrySet();
       List<Entry<Integer, Integer>> listOfentrySet = new ArrayList<Entry<Integer, Integer>>(entrySet);

       Collections.sort(listOfentrySet, new SortByValue());

       for(Map.Entry<Integer, Integer> entry:listOfentrySet)
       System.out.print(lMap.get(entry.getKey())+" ");

   }
}


class SortByValue implements Comparator<Map.Entry<Integer, Integer>>{

   @Override
   public int compare( Map.Entry<Integer,Integer> entry1, Map.Entry<Integer,Integer> entry2){

       int second=entry2.getValue();   //just change these 2 lines to get the order as required.
       int first=entry1.getValue();

          if(second>first)
            return 1;
          if(second<first)
            return -1;
          else
             return 0;


       //return (entry2.getValue()).compareTo(entry1.getValue() );
   }
}