C++太难用了，还是Java和Python好用。

//Java代码
import java.math.BigInteger;
import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        BigInteger a = sc.nextBigInteger();
        BigInteger b = sc.nextBigInteger();
        System.out.println(a.add(b));
        System.out.println(a.subtract(b));
        System.out.println(a.multiply(b));
    }
}
#Python代码
a = int(input())
b = int(input())
print(a + b, a - b, a * b, sep='\n')