题解 | #交换变量值#

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int a = scanner.nextInt();
        int b = scanner.nextInt();
        a=(a+b-(b=a));        //这是核心思想，把a转换成b了。
        //write your code here.......
        

        System.out.println(a+" "+b);
    }
}