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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}

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

Comments

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