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

int main(void)
{
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  ** * ** ***** *  ** * ** * 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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**    * **** * **  **  *** **      *  **
*  * * *******  *         *  OF YOUR CODE*/
}

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

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;
*  * *****  **** * * ****  **** ****  {
  *    **   * * **** *   * ** **  * ***    *  * *  * ***    
*  *** **  ***** ***  * **** **    *   *   ****** *****  *      * *  break;
  * *  * * ***  * **** **  *  *    *** ***  *  **    * *  *
 ** **  **  ** **  *     
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}

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

Comments

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