Program for Union and Intersection of integer array in Java

Find the Union and Intersection for the input arrays of: arr1[] = {7, 1, 5, 2, 3, 6} ,  arr2[] = {3, 8, 6, 20, 7}

Then your program should print Union as {1, 2, 3, 5, 6, 7, 8, 20} and Intersection as {3, 6, 7}. Note that the elements of union and intersection can be printed in any order.

import java.util.HashSet;

class Test

{   

    // Prints union of arr1[0..m-1] and arr2[0..n-1]

    static void printUnion(int arr1[], int arr2[])

    {

        HashSet<Integer> hs = new HashSet<>();

        for (int i = 0; i < arr1.length; i++) 

            hs.add(arr1[i]);        

        for (int i = 0; i < arr2.length; i++) 

            hs.add(arr2[i]);

        System.out.println(hs);        

    }

      

    // Prints intersection of arr1[0..m-1] and arr2[0..n-1]

    static void printIntersection(int arr1[], int arr2[])

    {

        HashSet<Integer> hs = new HashSet<>();

        HashSet<Integer> hs1 = new HashSet<>();

        for (int i = 0; i < arr1.length; i++) 

            hs.add(arr1[i]);

        for (int i = 0; i < arr2.length; i++) 

            if (hs.contains(arr2[i]))

               System.out.print(arr2[i] + " ");

    }

      

    // Driver method to test the above function

    public static void main(String[] args) 

    {

        int arr1[] = {7, 1, 5, 2, 3, 6};

        int arr2[] = {3, 8, 6, 20, 7};

  

        System.out.println("Union of two arrays is : ");

        printUnion(arr1, arr2);

        System.out.println("Intersection of two arrays is : ");

        printIntersection(arr1, arr2);        

    }

}