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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*** ***  *  * *            **  ***  
* * ** * * **   *    ***  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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{
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******  * ***** * ** ***  * *** has %d **** *** * **  ** *   
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}

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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}

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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** **   *** *** * 
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*    * **  *** * ** 
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}

Comments

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