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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   **      **  **  ***   * **        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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***  *** * * * **** **    ** 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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}

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 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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*    * *** **   **
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}

Comments

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