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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    *** * *     *  **  *** long int pow=1;
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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 2

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

int main(void)
{
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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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}

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 4

Hidden content!
#include <stdio.h>
int num_digits(int n)
{
* **  *  ** * * *         i;
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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 5

Hidden content!
#include  **   * ** 
int num_digits(int n)
{
   ***** *  * * ** *  ** i;
*  * **** **     * ** ** *  *    = 0;n!=0;i++)
** **    *     *  *    *    
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* * * * *** ** **   **     
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}

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