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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***** ***   *  *   **  *** *   * * * ****
*  ** *    * *      * 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)
{
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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)
{
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**      ** ** ***** ******  *  * 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

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