12-07 Exercise 2: Function num_digits

Question

Write a function num_digits(n) that returns the number of digits in n ( a positive integer). Hint: to determine the number of digits in a number n, divide it by 10 repeatedly. when n reaches 0, the number of divisions indicates how many digits n originally had.

寫一個num_digits(n)函數 計算n有幾位數

#include <stdio.h>
int num_digits(int n)
{
   /*INSERT YOUR CODE HERE*/

   /*在這裡寫你的程式*/
   /*END OF YOUR CODE*/
}

int main(void)
{
   int n;
   scanf("%d", &n);
   printf("%d has %d digit(s)",n,num_digits(n));
   return 0;
}

Please complete this program by only insert your code between those tags:

   /*INSERT YOUR CODE HERE*/ 
   /*END OF YOUR CODE*/

Example input

12347

Example output

12347 has 5 digit(s)

Remember: You may correct the cases, but your code always be revised!

Answer 1

Hidden content!
#include <stdio.h>
int num_digits(int n)
{
* *  ***   **   ** * *** * YOUR CODE HERE*/

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**  **    ** **** * ****** ** long int pow=1;
 *       ********  * *    * (n<0){
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*  **  ****  **** *  ****  ** 
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** *  *   ** *    * * *  ** * **  **
  **** ***** ****     ** OF YOUR CODE*/
}

int main(void)
{
   int n;
**   * ** ****   *  ** *** ***   *  **   &n);
**  * **   ***** *    * *    ** **  has %d ***  *  *****  *  ** *   
 *  **  * *  * **** * 0;
}

Comments

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output
Case 3: Correct output

Answer 2

Hidden content!
#include <stdio.h>
int num_digits(int n)
{
 ***** *    **   *  * i=0;
 ***  ** *  * * * ** ** **  *
***     *    *  ***  
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*   *    *  ***     * ***** YOUR CODE HERE*/

* * *   *      * ** **   * ***  *   *  *  *
 ***  *     *  *    * * OF YOUR CODE*/
}

int main(void)
{
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* **     *  ******  *  ** * * *  ***    * * * &n);
 *  **** *** *  ** *  ** * *   has %d *    * ** *   *   ***
*   * *** ** ** ******   **   0;
}

Comments

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output
Case 3: Correct output

Answer 3

Hidden content!
#include <stdio.h>
int num_digits(int n)
{
**  *  * **** *       * ** counter=1;
  *  ***  **   **** *****   **  ** * ** * 
  *** * **  **   * **   ** *   * *    * ** * **  * * 
**** * ***** * *  *   ****   ** *  * *  ***   * ***    *  
    **            **** **
     ****  *  ***   *****  *    counter;
}

int main(void)
{
** ** * **    **    *   * n;
 * ***     *  *  *   * * *  *   &n);
   ** * *   ****   * **       * * has %d *   * *  ***    **  * 
*    *  * **   *   *   **** 0;
}

Comments

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output
Case 3: Correct output

Answer 4

Hidden content!
#include <stdio.h>
int num_digits(int n)
{
  *  *   **  * *    * *  *   i;
*  * *   *     ***** ***    **    {
  * *** * *     *** * ***  ** *****  *** ***** 
    *   **  **  *    * ****  * *  * *   * * **   **  ** break;
**  * **   **** **   * *****  ** ***   * ***** * *   * 
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 ***    ** * ** ** **** *  **  *    i;
}

int main(void)
{
** * *********    ** n;
* *   * **  ***    * * * *  *  * ****   *  &n);
  ***       **    ** ** ** * **  has %d ****   * * *    **** 
* *   ** **    * * * **    0;
}

Comments

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output
Case 3: Correct output

Answer 5

Hidden content!
#include  **  *  **  *   
int num_digits(int n)
{
 * * * ***  ** *** * i;
*  ****     ** *  *  ***  *** * * = 0;n!=0;i++)
*   ** **    *  *   *   *  
 *        ** *  ** *** *  **     ** **  *    **  *   * * *** = n / 10;
***** ***  * *  *   *** **  **
*  ***** ** ****  *** *   **** i;
}

int main(void)
{
***  **     **** *****   *  n;
* *  ** * **** * **   * *** *** ****  &n);
  **   * ***** **  *
 ** ** ***  * ** * ****   * ***** has %d   *   ***** **   **  **   * 
 ***  * *       * * *  **
* **   **    **  *  ** *  0;
}

Comments

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output
Case 3: Correct output