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)
{
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***   *  * ** *  *  *   OF YOUR CODE*/
}

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

Answer 2

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

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)
{
*** * ** * * *   ***** ** * i;
* ***     *    *    *    {
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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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*     * * *             
  **    *  **    *  **** 0;
}

Comments

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