怎么写呀 直接交换为什么不行啊 大家帮我看看吧

img


Scanner scanner = new Scanner(System.in);
        int a = scanner.nextInt();
        int b = scanner.nextInt();
        if(b>a){
            System.out.println(a + " " + b);
        }
        else{
            System.out.println(b + " " + a);
        }