java - 尝试使用 int Java 反转 123 _> 321

Question

我的任务是创建一个方法，该方法将从用户处获取 3 位数字输入并反转其顺序，然后以新顺序将其返回，而不将任何内容转换为字符串，它全部保留为 int。我无法弄清楚如何在不将值相加的情况下返回新数字(第一第二第三)；

public class Lab01
{

   public int sumTheDigits(int num)
   {
      int one;
      int two;
      int three;

      one = num % 10;
      two = (num/10) % 10;
      three = num / 100;

      return one + two + three;
   }

   public int reverseTheOrder(int num)
   {
      int first;
      int second;
      int third;

      third = num / 100;
      second = (num/10) % 10;
      first = num % 10;


      return ?;
   }

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

      Lab01 lab = new Lab01();
      System.out.println("Enter a three digit number: ");
      int theNum = input.nextInt();
      int theSum = lab.sumTheDigits(theNum);
      int theReverse = lab.reverseTheOrder(theSum);

      System.out.println("The sum of the digits of " + theNum + " is " + theSum);
      System.,out.println(theNum + " reversed is " + theReverse);



   }

}

Answer 1

您可以尝试以下任意数字长度

public static void main(String args[]) {
        int num = 0;
        int reversenum = 0;
        System.out.println("Enter number: ");
        Scanner in = new Scanner(System.in);
        num = in.nextInt();
        while (num != 0) {
            reversenum = reversenum * 10;
            reversenum = reversenum + num % 10;
            num = num / 10;
        }

        System.out.println("Reverse number is: " + reversenum);
    }