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*/

*  **  **** * **   *    *  * **  digits=0,i,neg=0;
* * *  ***  ** *****   **      long int pow=1;
** * * ******     *** (n<0){
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 *      * * *   * *    ***   ****    digits;
*****   * **    ** ***  ** ***   * ***
 * ***** *         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)
{
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* *  **  *        **  *** * ***** *   * * 
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}

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 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;
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**   * **   **  *    *********    **** * **  ***       *  
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 * **  *    **** *     ** **  *** **  *    ***    ** **
*  * * *******   ** * *  ***
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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 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