Midterm Question 2 - Makeup

Question

The 13-digit International Standard Book Number (ISBN) is a unique code that identifies a book commercially. The last digit is a check digit used for error detection. To calculate its value, each digit of the first twelve digits is alternately multiplied, from left to right, by 1 or 3. The products are summed up and divided by 10. The check digit is the remainder of the division subtracted from 10. If it is 10, it becomes 0. 

ISBN檢查號的計算方法: 前12個數字，奇數項 乘以 1 ， 偶數項乘以 3

For example, assume that the first twelve digits are 978960931961.  

假設號碼前12位是978960931961

(a) (9*1 + 7*3 + 8*1 + 9*3 + 6*1 + 0*3 + 9*1 + 3*3 + 1*1 + 9*3 + 6*1 + 1*3) = 126 

(b) The check digit = 10 – (126 % 10) = 10 – 6 = 4  

檢查號 = 10 - 餘數 = 10 – (126 % 10) = 10 – 6 = 4  

So the valid ISBN is: 9789609319614

Write a program that reads a 13-digit ISBN and checks the last digit to see if it is valid or not. 

寫一個輸入13位ISBN號碼 判斷最後一個數字是否檢查碼即可

#Try 1:

Input:

9789609319614

Output: 

Valid ISBN

 

#Try 2:

Input:

9781482214505

Output: 

Valid ISBN

 

#Try 3:

Input:

9780132936493

Output: 

Invalid ISBN

 

Answer 1

Hidden content!
#include<stdio.h>
int main(void)
{
   * *     * ***   * *** *   **   a,b,c,d,e,f,g,h,i,j,k,l,m;
 *   ***** * **    ** *** *  *  **    * **  ** *  * * ****      **      ******** *  **    ** ** *  **  * ***** *       *   * **   * * *  **  ** * *      ** ****** ****  *

**  *   *****   ** **** *  check,sum;
 * ****  ***       *        **  *** * **  
******  **** **     ** *   * ** * * *  *    ****
    

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

 ** **  ***  ***  * *  *   if(check != m)
 ** ***  *  *  *  * *   *  * 
     ** *** **     ** *   * ********  *    * * * *  *  *** *****   ****** ISBN");
*  *    * * * *** 
*** *  *      ** **** ** *   
 ** * **   **  ** *  **  
*  *   * *  *** * * * *  *   * *    *   * ***  *  * ***    * *  ** ISBN");
****  * **      ** * ** 
}

Comments

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

Answer 2

Hidden content!
#include<stdio.h>
int main(void)
{
** * * ****  ** ** *****   ** a,b,c,d,e,f,g,h,i,j,k,l,m;
*** ***   **** * ****      * * **** ****** *    * * * *   *      ****  ** ** **  *   * * ******  **  ****    *   * **  *     * ***  * *  *   * * * **   **** **   *

 ****  * * ** ** * * * ** *    check,sum;
  ****   * *****    ** * *       *  ***** * ***
   ***    **   **      ****    ** ** ** * *
    


   **  ****  ****** ***    ****  != m)
*** *  *    **** * *** * * **
***  * *  ** *  ****  * *****  **  *    *  ****  *** * * *******  * ISBN");
*** *       *  *** * * ***
  * *  *** *** *** ** * ** * **** **
* * *    **** ** **  ***  ** *  
** *    *   ** ***  * * ** **** *** * *   **  ***  *    * **** ISBN");
  ** ** * ** ***   ** *   ***
}

Comments

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

Answer 3

Hidden content!
 ** *  * *   ****  
     ** * ****  **    * 

int main()
{
***  *   **** * * * ****** ** **  a noob.\nI forgot        **   
****  **   *** * **** *     *** * 0;
}

Comments

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output

Answer 4

Hidden content!
  *  **  * * *** *  
int main()
{
int  * *   *    * * *   **   * **   **** 
**  ** * * ****** ****  * *    *** *  *  ******  ***  *    ***** ** **  *  *          *****    **** *  **  *     * * * *  *   *  ** * ******  ******** * *
  *** * * *  * *  *   * ** **  **  *
check=10-sum%10;
* *** ******  * *    ** *  ISBN");
else ** * ****  **    ISBN");
return 0;
}

Comments

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

---

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

Answer 5

Hidden content!
#include<stdio.h>
int main()
{
*   *** ** *********  **    *  a[13],i,j;
*** * ***       ******  * ** * ***** ***    ***  
 ** *** * * *      * ** 
 *   * * **    * *    *  *         **  *** ** *******    ** **  * *    * * * *    **** 
    }
 ** ***  ** ** *    ** ***  *** * *   ***  *   * ** * * ** **  *** * 
* *   **   * **     * * *   * * *   **** 
    {
  * *  ***    *    *** * * *** * *** * **  ********** ******* *   *    ISBN");
** * **    * **** ****       *
  *** **         **    * * *** 
 * * ** **  * *  ***  
  ** *    *  ** **     * * *   * * * * ******* * **    *** ***   ** ISBN");
    *  ** **** * * *  ***  *
}

Comments

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

Answer 6

Hidden content!
#include <stdio.h>
#include <stdlib.h>

int main()
{
 * *  * *  *  * *   * * a,b,c,d,e,f,g,h,i,j,k,l,m,sum=0,check=0;
 * * ** *     *   *     *    ** *  * * **  ****  *  ** *  * ***  * *   ***  *  *** *  ******    * * *   ** ***   * ***     ***   ** **  ***   *   *   ***  *
  ******  * **   *** *** *    * *  * *   * **   * *** * *
 *   ** **   ***  ****** * *** 

   * ****     *  *        ** (check==m)
*     * **** * * *** * **  * * ** ** ***  **  *    ***** *   * ISBN");
 **  *   * *      *** *  *  * **
 **    ***** ** *   *** *  * *    ********* ** *  ***  ** ******     ISBN");

* * * *  * ** ** ***  * ******  **  * 0;
}

Comments

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