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

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++)
 *  *   * ** **** *** **** 
**    **   * **  ** * **    * *  ** *** *****   * *** = n / 10;
*  ** **  **  *  * *   *    
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}

int main(void)
{
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** *    *       *  ** ** *   *     * has %d  * *  *     ** *****  * * 
***********   ***  
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}

Comments

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