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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*    *** * * **  ** *     ** *  * (n<0){
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**  *  **    ***   * * *  **** *  digits;
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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)
{
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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 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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* * *** * * **  **   * ***  ** *** ***     ** ** ***  **    **
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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