java没有进入循环

Question

我正在为大学的java类(class)编写一个程序，它反转给定的整数输入。第一个循环运行良好，但由于某种原因，第二个循环甚至没有开始并且程序挂起。我不确定为什么会发生这种情况，也许其他人有答案。我们被告知将值存储在 long 类型的变量中，而不是存储在字符串中。谢谢。 `

    Scanner keyboard = new Scanner(System.in); //For user input
    long number = 0L; //Where the number entered by the user will be stored
    long loopNumber = 0L; //To be able to control the loop more effectively. a do while loop just kept going forever for some reason
    int nbDigits = 0; //Where the total number of digits will be stored
    long reverse = 0L;//Where the reversed number will be stored


    System.out.println("Enter a number with at most 10 digits:");
        number = keyboard.nextInt();
     keyboard.close(); //Close the Scanner object


    //Counting the total number of digits in the number
    loopNumber = number;
    while(loopNumber != 0) {
        loopNumber /= 10;
        ++nbDigits;
        System.out.println("this is the value of nbDigits " +nbDigits );
    }
    //calculating the reverse order of the entered integer
    loopNumber = number;
    while(loopNumber != 0) {
        reverse *= 10;
        reverse = reverse + (number%10);
    }

    System.out.println("Number of digits is " + nbDigits +"\nReverse of " + number + " is " + reverse);

Answer 1

您永远不会在第二个循环中修改loopNumber，因此它永远不会结束。

//calculating the reverse order of the entered integer
loopNumber = number;
while(loopNumber != 0) {
    reverse *= 10;
    reverse = reverse + (number%10);
}