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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

 

[Exam] asked in Midterm by (12.1k points)
ID: 36751 - Available when: 2017-11-15 14:10 - Due to: Unlimited
| 5.7k views

26 Answers

0 like 0 dislike
Hidden content!
#include<stdio.h>

int main(){
    char isbn[12];
    int a,b,c,d,e,f,g,i=0,j;
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answered by (-32 points)
0 0
Case 0: Wrong output
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Case 3: Wrong output
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Hidden content!
#include<stdio.h>

int main(){
    char isbn[12];
    int a,b,c,d,e,f,g,i=0,j;
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answered by (-32 points)
0 0
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
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Hidden content!
#include <stdio.h>
#include <string.h>

int main(){
    ///long long int n = 978960931962;

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90/100 answered by (-74 points)
0 0
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
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}
answered by (-107 points)
0 0
prog.c: In function 'main':
prog.c:9:7: warning: too many arguments for format [-Wformat-extra-args]
 scanf("%13d",&num1,&num2,&num3,&num4,&num5,&num6,&num7,&num8,&num9,&num10,&num11,&num12,&num13);
       ^~~~~~
0 like 0 dislike
Hidden content!
#include ** * *** * ***


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answered by (-107 points)
0 0
prog.c: In function 'main':
prog.c:9:7: warning: too many arguments for format [-Wformat-extra-args]
 scanf("%13d",&num1,&num2,&num3,&num4,&num5,&num6,&num7,&num8,&num9,&num10,&num11,&num12,&num13);
       ^~~~~~
0 like 0 dislike
Hidden content!
#include<stdio.h>
int main()
{
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answered by (-233 points)
0 0
prog.c: In function 'main':
prog.c:5:14: warning: format '%ld' expects argument of type 'long int *', but argument 2 has type 'int *' [-Wformat=]
     scanf("%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld", &a1,&a2,&a3,&a4,&a5,&a6,&a7,&a8,&a9,&a10,&a11,&a12,&a13);
              ^
prog.c:5:17: warning: format '%ld' expects argument of type 'long int *', but argument 3 has type 'int *' [-Wformat=]
     scanf("%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld", &a1,&a2,&a3,&a4,&a5,&a6,&a7,&a8,&a9,&a10,&a11,&a12,&a13);
                 ^
prog.c:5:20: warning: format '%ld' expects argument of type 'long int *', but argument 4 has type 'int *' [-Wformat=]
     scanf("%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld", &a1,&a2,&a3,&a4,&a5,&a6,&a7,&a8,&a9,&a10,&a11,&a12,&a13);
                    ^
prog.c:5:23: warning: format '%ld' expects argument of type 'long int *', but argument 5 has type 'int *' [-Wformat=]
     scanf("%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld", &a1,&a2,&a3,&a4,&a5,&a6,&a7,&a8,&a9,&a10,&a11,&a12,&a13);
                       ^
prog.c:5:26: warning: format '%ld' expects argument of type 'long int *', but argument 6 has type 'int *' [-Wformat=]
     scanf("%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld", &a1,&a2,&a3,&a4,&a5,&a6,&a7,&a8,&a9,&a10,&a11,&a12,&a13);
                          ^
prog.c:5:29: warning: format '%ld' expects argument of type 'long int *', but argument 7 has type 'int *' [-Wformat=]
     scanf("%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld", &a1,&a2,&a3,&a4,&a5,&a6,&a7,&a8,&a9,&a10,&a11,&a12,&a13);
                             ^
prog.c:5:32: warning: format '%ld' expects argument of type 'long int *', but argument 8 has type 'int *' [-Wformat=]
     scanf("%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld", &a1,&a2,&a3,&a4,&a5,&a6,&a7,&a8,&a9,&a10,&a11,&a12,&a13);
                                ^
prog.c:5:35: warning: format '%ld' expects argument of type 'long int *', but argument 9 has type 'int *' [-Wformat=]
     scanf("%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld", &a1,&a2,&a3,&a4,&a5,&a6,&a7,&a8,&a9,&a10,&a11,&a12,&a13);
                                   ^
prog.c:5:38: warning: format '%ld' expects argument of type 'long int *', but argument 10 has type 'int *' [-Wformat=]
     scanf("%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld", &a1,&a2,&a3,&a4,&a5,&a6,&a7,&a8,&a9,&a10,&a11,&a12,&a13);
                                      ^
prog.c:5:41: warning: format '%ld' expects argument of type 'long int *', but argument 11 has type 'int *' [-Wformat=]
     scanf("%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld", &a1,&a2,&a3,&a4,&a5,&a6,&a7,&a8,&a9,&a10,&a11,&a12,&a13);
                                         ^
prog.c:5:44: warning: format '%ld' expects argument of type 'long int *', but argument 12 has type 'int *' [-Wformat=]
     scanf("%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld", &a1,&a2,&a3,&a4,&a5,&a6,&a7,&a8,&a9,&a10,&a11,&a12,&a13);
                                            ^
prog.c:5:47: warning: format '%ld' expects argument of type 'long int *', but argument 13 has type 'int *' [-Wformat=]
     scanf("%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld", &a1,&a2,&a3,&a4,&a5,&a6,&a7,&a8,&a9,&a10,&a11,&a12,&a13);
                                               ^
prog.c:5:50: warning: format '%ld' expects argument of type 'long int *', but argument 14 has type 'int *' [-Wformat=]
     scanf("%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld%ld", &a1,&a2,&a3,&a4,&a5,&a6,&a7,&a8,&a9,&a10,&a11,&a12,&a13);
                                                  ^
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Hidden content!
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}
answered by (-107 points)
0 0
prog.c: In function 'main':
prog.c:9:7: warning: too many arguments for format [-Wformat-extra-args]
 scanf("%13d",&num1,&num2,&num3,&num4,&num5,&num6,&num7,&num8,&num9,&num10,&num11,&num12,&num13);
       ^~~~~~
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}
answered by (-107 points)
0 0
prog.c: In function 'main':
prog.c:8:11: warning: format '%d' expects argument of type 'int *', but argument 2 has type 'int' [-Wformat=]
 scanf("%13d",num1,num2,num3,num4,num5,num6,num7,num8,num9,num10,num11,num12,num13);
           ^
prog.c:8:7: warning: too many arguments for format [-Wformat-extra-args]
 scanf("%13d",num1,num2,num3,num4,num5,num6,num7,num8,num9,num10,num11,num12,num13);
       ^~~~~~
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Hidden content!
#include<stdio.h>
int main(void)
{
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}
answered by (-249 points)
0 0
Case 0: Correct output
Case 1: Correct output
Case 2: Correct output
Case 3: Correct output
0 like 0 dislike
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answered by (16 points)
0 0
prog.c: In function 'main':
prog.c:6:9: warning: format '%d' expects argument of type 'int *', but argument 2 has type 'int' [-Wformat=]
 scanf("%d%d%d%d%d%d%d%d%d%d%d%d",i1,i2,i3,i4,i5,i6,i7,i8,i9,i10,i11,i12);
         ^
prog.c:6:11: warning: format '%d' expects argument of type 'int *', but argument 3 has type 'int' [-Wformat=]
 scanf("%d%d%d%d%d%d%d%d%d%d%d%d",i1,i2,i3,i4,i5,i6,i7,i8,i9,i10,i11,i12);
           ^
prog.c:6:13: warning: format '%d' expects argument of type 'int *', but argument 4 has type 'int' [-Wformat=]
 scanf("%d%d%d%d%d%d%d%d%d%d%d%d",i1,i2,i3,i4,i5,i6,i7,i8,i9,i10,i11,i12);
             ^
prog.c:6:15: warning: format '%d' expects argument of type 'int *', but argument 5 has type 'int' [-Wformat=]
 scanf("%d%d%d%d%d%d%d%d%d%d%d%d",i1,i2,i3,i4,i5,i6,i7,i8,i9,i10,i11,i12);
               ^
prog.c:6:17: warning: format '%d' expects argument of type 'int *', but argument 6 has type 'int' [-Wformat=]
 scanf("%d%d%d%d%d%d%d%d%d%d%d%d",i1,i2,i3,i4,i5,i6,i7,i8,i9,i10,i11,i12);
                 ^
prog.c:6:19: warning: format '%d' expects argument of type 'int *', but argument 7 has type 'int' [-Wformat=]
 scanf("%d%d%d%d%d%d%d%d%d%d%d%d",i1,i2,i3,i4,i5,i6,i7,i8,i9,i10,i11,i12);
                   ^
prog.c:6:21: warning: format '%d' expects argument of type 'int *', but argument 8 has type 'int' [-Wformat=]
 scanf("%d%d%d%d%d%d%d%d%d%d%d%d",i1,i2,i3,i4,i5,i6,i7,i8,i9,i10,i11,i12);
                     ^
prog.c:6:23: warning: format '%d' expects argument of type 'int *', but argument 9 has type 'int' [-Wformat=]
 scanf("%d%d%d%d%d%d%d%d%d%d%d%d",i1,i2,i3,i4,i5,i6,i7,i8,i9,i10,i11,i12);
                       ^
prog.c:6:25: warning: format '%d' expects argument of type 'int *', but argument 10 has type 'int' [-Wformat=]
 scanf("%d%d%d%d%d%d%d%d%d%d%d%d",i1,i2,i3,i4,i5,i6,i7,i8,i9,i10,i11,i12);
                         ^
prog.c:6:27: warning: format '%d' expects argument of type 'int *', but argument 11 has type 'int' [-Wformat=]
 scanf("%d%d%d%d%d%d%d%d%d%d%d%d",i1,i2,i3,i4,i5,i6,i7,i8,i9,i10,i11,i12);
                           ^
prog.c:6:29: warning: format '%d' expects argument of type 'int *', but argument 12 has type 'int' [-Wformat=]
 scanf("%d%d%d%d%d%d%d%d%d%d%d%d",i1,i2,i3,i4,i5,i6,i7,i8,i9,i10,i11,i12);
                             ^
prog.c:6:31: warning: format '%d' expects argument of type 'int *', but argument 13 has type 'int' [-Wformat=]
 scanf("%d%d%d%d%d%d%d%d%d%d%d%d",i1,i2,i3,i4,i5,i6,i7,i8,i9,i10,i11,i12);
                               ^
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[Exam] asked Dec 9, 2017 in Midterm by thopd (12.1k points)
ID: 36755 - Available when: 2017-11-15 14:10 - Due to: Unlimited
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