10-19 Exercise 1: International Standard Book Number (ISBN)

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()

{
**** **** * * * *** * ** * ** ***
* **** * *** * ** * * * ** * ** *** ***** **** ** * ** **** ** **** ** * * ** **** * ***** *** *** * * ** ** * * ** ****** **** * * * *
** *** * ******* **** **** *** * *** * ** * * * * * *


* * **** ***** * **** ** **
***** *** *** * ** * * * ** * ** ** * ** ISBN");
* ** * **** **** * *** **

   else
**** ** * **** * ** ****** * *** **** ***** * ISBN");

   
* *** *** ** * *** * ** **** ** * * * 0;



}

Comments

prog.c: In function 'main':
prog.c:11:4: error: this 'else' clause does not guard... [-Werror=misleading-indentation]
    else
    ^~~~
prog.c:14:8: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'else'
        return 0;
        ^~~~~~
cc1: all warnings being treated as errors

Answer 2

Hidden content!
#include <stdio.h>

int main()

{
* * * * * *** * **** * * ** * ** **** **** ****
***** * * **** * * * ** *** *** * ** ** * ** *** ** * * ****** * **** ** ** ******* ** * * ** * * * **
** * * * * ** ** ** ** ** ***** *** **** ** * * * ** ***


*** **** * ** ** * * * *
* ** ** * ** * * * ** *** ****** *** * **** ****** ** * * * * ISBN");
* * * * **

   else{
** ** * * * ** * ** ** * * ***** * ** * *** * ISBN");

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



}

Comments

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

Answer 3

Hidden content!
#include <stdio.h>

int main()

{
* * ** ** ** ** *** * ****** * ********** * *** *
*** * * *** * **** * * *** * ** ****** * *** **** * **** * * * ** * ** *** ** * * ** ** * ** ***** ** *** ** **** **** * *** *** * ***
* * * *** * ** *** ** ***** * ******* **** * **** ***** ****** ***

   if (b12==total)
** ** *** ** ** * * ** * *** ** *** *** ** **** * * ISBN");

   else
* * ** * ** *** * * * ** ***** *** * * ** * ********* ** ISBN");


* * * * * *** * ** * ** * ***** * * ** * ** 0;



}

Comments

prog.c: In function 'main':
prog.c:9:4: error: this 'else' clause does not guard... [-Werror=misleading-indentation]
    else
    ^~~~
prog.c:12:8: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'else'
        return 0;
        ^~~~~~
cc1: all warnings being treated as errors

Answer 4

Hidden content!
#include <stdio.h>

int main()

{
** * *** ** * *** * *** * * **** * *** ** **
* *** ** * * * * * ** *** * * * * * ** * ** ** **** ** *** * ** * * * * *** ** ***** ** * *** ** * ** ****** **** ** **** * *** * ****** *
* *** ***** * * * ** **** * * * * ** **** ** ** **** * **** *

   if (b12==total)
* * ******* ** * * ** ** * * ** * * * * ******* * ** * ISBN");

   else
* ** *** * ** * * * ** * ****** * ** ** * * ** **** * ISBN");


* * * ** * * * * ** * *** * * * 0;



}

Comments

prog.c: In function 'main':
prog.c:9:4: error: this 'else' clause does not guard... [-Werror=misleading-indentation]
    else
    ^~~~
prog.c:12:8: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'else'
        return 0;
        ^~~~~~
cc1: all warnings being treated as errors

Answer 5

Hidden content!
include <stdio.h>
int main()
{
  * ******  * *** *    * * * *   **      *** **  ** *  
   * * **  ****** *  ** ****  ** **   **     **  *     *     **    * ****  *  ** **** **  * ****     *   **      ** ***  * ****   *** **   ****  **     *** * ** * **  ****  *
 **  *  *     *  *  * *** * *  *  * *** * ** ********  *   * *  ***** 
   if (b12==total)
**** * *** * *****  *  *   *  ** *    *** * * **** ** *   *  *  * ***  * *  *** ISBN");
   else
*   * *** *  **  *** * ** ****    *  * * **  * *  * **  **  ** * *  ** ISBN");

***   * ** ** **  *  * ** **  ** **  *  ***   0;

}

Comments

prog.c:1:9: error: expected '=', ',', ';', 'asm' or '__attribute__' before '<' token
 include <stdio.h>
         ^

Answer 6

Hidden content!
#include   **** ****  ***
int main()
{
 *   *           *  ** * **       **    *** ****** * ***    
 **     * *      * **** *  *     ** **    * *   * **  **  **** **      *   **  * * * ** *   ****  * ****  *  ** *   * **** * ** ****   *  *** ** ***** *  * *  *  *  *  * 
 *   **  **  *** **     * *  *  sum = ( 1) * (a1+a3+a5+a7+a9+a11);
  *  *  ***     **   ***  * * sum2 =  (3) *  ** ** ***** 
    * *** ******  *  ** *  ** sum3 = sum + sum2;
  ***** ** ** *  **   *  *  check = 10 - (sum3 % 10);
*    ** ***  *  ***  **** * *** == a13)  {
 * * *   *     *  ***  * *      *    * **  **** *** * * *  *  ISBN");}
 *    * *  *  * *  * *** *  **   **** *  *** *  **  **   **  ***    *  * *** ISBN");}
return 0;
}

Comments

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

Answer 7

Hidden content!
#include <stdio.h>
int main()
{
****    * * *    *** * *     *   * ***   ***  **

  ** ****     ***   **    * ************* *  **  ** *  ** **  **  ***    *  **  ** *  ***    ***   ******    * * ***** * * *    ** ****    **    *** **  *****

*   *****     **   = ** * ** *  * ** ***   **  * *   * * ***    *** 




 * *** ***** (last==checkk)
** * ***  * ** * ***  *  ** **  ******* *** ISBN");
*  * * ** ***** *
  * ** *   ** *********        * **** ISBN");

* **    ****   *** 0;

}

Comments

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

Answer 8

Hidden content!
#include *     ** **** *
int main()
{
* **  * ****** * ** * ** *  *  **  ***  *   *** ** ** **
**** * *     ** ** ** *****  *  *  **** ****  ****** ***     * * * *******   ** ***** * * **     **   *  *** *** ****    * * ** ** **  **  *  ****    *** ****** **  ** ** ****  
**  **  **   *  * ** ** ** sum = ( 1) * (a1+a3+a5+a7+a9+a11);
   ** ** *    *   **  *   *  *** sum2 =  (3) * (a2+a4+a6+a8+a10+a12);
   **  * *      *  * * *      sum3 = sum + sum2;
*  *  * * ***   *  * ******* check = 10 - (sum3 % 10);
**** ** * *** **   * *** ***** *    *** == a13)  {
* ** **   * *** *     * ** **** *****   * ** *    * * ******  **  * * ** *  ** ** *
* * *** **** *** ** **** * *****    *  * ** *****     *** ***** ** * **  *  **** *  * *
return 0;
}

Comments

prog.c: In function 'main':
prog.c:11:16: error: too many arguments for format [-Werror=format-extra-args]
         printf("Valid ISBN",check);}
                ^~~~~~~~~~~~
prog.c:12:22: error: too many arguments for format [-Werror=format-extra-args]
         else {printf("Invalid ISBN",check);}
                      ^~~~~~~~~~~~~~
cc1: all warnings being treated as errors

Answer 9

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

* ***    * * *   *  ** **  *  ***   
* **  *  ***  ** * * **  *** *  * * ** *
 ** **** **    *  * **    ***    *    
* * ** *** ** *  * ***    ****  ** *   *   * *
   *** **   ****  *** *** * *  *   *    *
     ****** * * **    **   ** ******  **
***** **   ***  *** *****  * ***
 *  * *  *** ** * *  * **  *    *   * 
  ***     *  *  ** * ** * ******   *
 **** ** *** * *  * *   *   *  ** * ** ** *
     *      *  *     * * * * ***** **
 ***** * *** **  *    * ** * ** *   ** ** 

  ** ** * **   *   * ***   ***   *  (m==10-(a+b+c+d+e+f+g+h+i+j+k+l)%10)
*  *** *  *  ** ****   *   ** **   
   **  * * ****  * *   * ***  *     ** ** *      *  * ****** *** *   ** *** ISBN");
     }
  * *     *  **   **** * ******* **
     {
 **        *   * *** **  * * **  * * * *  ** *  * **    * * * ** **** ** *  * ISBN");
     }
}

Comments

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

Answer 10

Hidden content!
#include  * * **  ** * 
int main()
{
*  ***** ***** *        * **     *  **       **  ** *   *** **** 
    ** ****  * *   **  ***  *   * ** *   * * * * *****   *  ****   * *   *  * *  *   **  **    *  ** * *  *******  * * *    ***  *   * **   *    *    ***  **   ******  *** ***
* **  ****** ** **** *** *    sum = ( 1) * (a1+a3+a5+a7+a9+a11);
 * *********** ** *   ** * *  sum2 =  (3) * (a2+a4+a6+a8+a10+a12);
* ****   * * *  * **    *   **** sum3 = sum + sum2;
 *      ** *    *    *   * *** check = 10 - (sum3 % 10);
 ***** *****  ***  * *  ****    *** == a13)  {
 *** *** *    ** *   *  ***** *  ***** *** *   ** * * *** *  ***     **   *    ***  *  ** *****  
*  ** *******   * **    **  ** ***** *   * * ******* *   * **** * * *   *  * ***         *
return 0;
}

Comments

prog.c: In function 'main':
prog.c:11:16: error: too many arguments for format [-Werror=format-extra-args]
         printf("Valid ISBN",check);}
                ^~~~~~~~~~~~
prog.c:12:22: error: too many arguments for format [-Werror=format-extra-args]
         else {printf("Invalid ISBN",check);}
                      ^~~~~~~~~~~~~~
cc1: all warnings being treated as errors