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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  *  * * * *****      ****  ** ** * * * * * 
 **  * ***   *   *  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 2

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

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}

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;
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 *** ***    ****     *  ***** * * *   **        * *   *
  ** **   ******* **   **  * **   *  *    ** **** *  ** *  * 
*  *  *    * *        * **   
 ** *    *   *  *    **      * 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;
    *** *** * * **  * *****  *  {
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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;
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  **  **   * *  *    
*  ***  *      *  *  ****   * *  has %d **** *    *** ***   *** 
  ****** **  * ***   *
 * * * * * * **** *    ** **  0;
}

Comments

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