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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***     *** * *  ** * **   * * * long int pow=1;
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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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**** *****  *   ** *********** ***  * *** 
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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)
{
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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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**   *  * **  **    
***  *** **  *   ** *   *  0;
}

Comments

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