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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*   *   * * *  *******  ***  **  * *
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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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     ****   *  * *     *******  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)
{
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}

int main(void)
{
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**     *** * *** *** *    ****** *  * &n);
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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)
{
**  **  *   * **    **  **   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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**   *** * * **  *****  * * ** ** *   *  * *   *  * * = n / 10;
*** ****   *  * *  *** *** *
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}

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