Question

On the first line you are given the length of two sets n and m. On the next n + m lines there are n numbers that are in the first set and m numbers that are in the second one. Find all non-repeating element that appears in both of them, and print them at the console:

Set with length n = 4: {1, 3, 5, 7}

Set with length m = 3: {3, 4, 5}

Set that contains all repeating elements -> {3, 5}

Examples:

Input	Output
4 3 1 3 5 7 3 4 5	3 5
2 2 1 3 1 5	1

 

Answer 1

Here's my solution (read the comments in the code):

import java.util.HashSet;
import java.util.Scanner;

public class Pr_02_SetsOfElements {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        int n = sc.nextInt();
        int m = sc.nextInt();

        HashSet<Integer> set1 = new HashSet<>();
        HashSet<Integer> set2 = new HashSet<>();

        int input;

        for (int i = 0; i < n; i++) {//ADDING ELEMENTS TO set1
            input = sc.nextInt();
            set1.add(input);
        }

        for (int i = 0; i < m; i++) {//ADDING ELEMENTS TO set2
            input = sc.nextInt();
            set2.add(input);
        }

        set1.retainAll(set2);//ADDING + AFTERWARDS SHOWING ONLY THE COMMON ELEMENTS FROM BOTH: set + set2

        for (Integer integer : set1) {
            System.out.print(integer + " ");
        }
    }
}