public class Solution {

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

    BigInteger num1 = sc.nextBigInteger();
    BigInteger num2 = sc.nextBigInteger();
    sc.close();

    System.out.println(num1.add(num2));
    System.out.println(num1.multiply(num2));
}

}

Remember import java.math.*;

Here's the code

import java.util.*;
import java.math.*;

public class Solution {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        
        BigInteger num1 = sc.nextBigInteger();
        BigInteger num2 = sc.nextBigInteger();
        sc.close();
        
        System.out.println(num1.add(num2));
        System.out.println(num1.multiply(num2));
    }
}

This is a great problem to get hands-on with Java's BigInteger class! It's amazing how easily it handles operations on numbers that go far beyond the range of standard data types. 11xplay black

Here is Java BigInteger solution - https://programmingoneonone.com/hackerrank-java-biginteger-problem-solution.html