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