Java:使用while-loop更改行的顺序

Question

我是编程新手，我想问我应该怎么做才能使k的最终值出现在a的值之前，当我试图将它放入循环中时，它会重复该语句，当我将它放在循环之前时，它的值是0。

    System.out.printf("Input an integer: ");
    int a = in.nextInt();
    int k = 0;
    
    System.out.print(a);
    while(a > 1)
    {
        if(a % 2 == 0)
            a = a / 2;
        else
            a = 3 * a + 1;
        System.out.printf(", " + a);
        k++;
    }
    System.out.println("\nk = " + k);


    Output:
    Input an integer: 10
    10, 5, 16, 8, 4, 2, 1
    k = 6

Answer 1

您可以尝试：

    System.out.printf("Input an integer: ");
    int a = in.nextInt();
    int k = 0;
    String str_a = "";
    
    System.out.print(a);
    while(a > 1)
    {
        if(a % 2 == 0)
            a = a / 2;
        else
            a = 3 * a + 1;
        str_a += ", " + String.valueOf(a);
        k++;
    }
    System.out.println("k = " + k);
    System.out.println("a = " + str_a);