Write a program to sort a map by value.

Description:

Sort or order a HashMap or TreeSet or any map item by value. Write a comparator which compares by value, not by key. Entry class might hleps you here.

Code:

? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 package com.govindsblog.algos;   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.Set; import java.util.Map.Entry;   public class OrderByValue {       public static void main(String a[]){         Map<String, Integer> map = new HashMap<String, Integer>();         map.put("java", 20);         map.put("C++", 45);         map.put("govindsblog", 2);         map.put("Unix", 67);         map.put("MAC", 26);         map.put("Why this kolavari", 93);         Set<Entry<String, Integer>> set = map.entrySet();         List<Entry<String, Integer>> list = new ArrayList<Entry<String, Integer>>(set);         Collections.sort( list, new Comparator<Map.Entry<String, Integer>>()         {             public int compare( Map.Entry<String, Integer> o1, Map.Entry<String, Integer> o2 )             {                 return (o2.getValue()).compareTo( o1.getValue() );             }         } );         for(Map.Entry<String, Integer> entry:list){             System.out.println(entry.getKey()+" ==== "+entry.getValue());         }     } }

Output:

Why this kolavari ==== 93 Unix ==== 67 C++ ==== 45 MAC ==== 26 java ==== 20 govindsblog==== 2

Write a program to find common elements between two arrays.

Description:

Write a program to identify common elements or numbers between two given arrays. You should not use any inbuilt methods are list to find common values.

Code:

? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 package com.govindsblog.algos;   public class CommonElementsInArray {       public static void main(String a[]){         int[] arr1 = {4,7,3,9,2};         int[] arr2 = {3,2,12,9,40,32,4};         for(int i=0;i<arr1.length;i++){             for(int j=0;j<arr2.length;j++){                 if(arr1[i]==arr2[j]){                     System.out.println(arr1[i]);                 }             }         }     } }

Output:

4 3 9 2