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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* * ** * **** ***** * 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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*** ***  ** *    *    ** ***** 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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*  **  *   **     ** *  * *      *   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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   * *     ** **  **     
 *   *  *  ***    **  * 0;
}

Comments

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