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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***  **  *****  **  **     ** 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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 **        **  *   ** ** *    *** *** *** * **      *  *** *  *
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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 4

Hidden content!
#include <stdio.h>
int num_digits(int n)
{
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* *   *    **** * * **   *     **   ** ** * **** *** ***  *
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   *  **    *******  * * * *   **  ** i;
}

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

Comments

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