Thread: isbn number.

i need help with the error

Code:

#include <stdio.h>
#include <stdlib.h>
#define size 11

int check(int a[size]);

int main()
{
   char a[size],
        i,
        x;

   printf("Enter 10 character ISBN number (Do Not Separate ISBN Characters With"
          "Spaces): \n\n");

   for(i=0; i<=10; i++)
      a[i]=getchar();

   x=check();

   if(x==a[9])
      printf("ISBN is valid.");
   else
      printf("ISBN is invalid");


   system("PAUSE");
   return 0;
}

int check()
{
   int sum,
       x,
       y=0;

   for(i=0; i<=9; i++)
      a[i]=a[i]-48;
   for(i=0; i<=9; i++)
   {
      x=y+(i+1)*a[i];
      y=x;
   }
   sum=x%11;
   return sum;
}

what errors are you getting? More details would be nice.

look at the prototype for check.

Originally Posted by xxbleh

i need help with the error

Code:

#include <stdio.h>
#include <stdlib.h>
#define size 11

int check(int a[size]);

int main()
{
   char a[size],
        i,
        x;

   printf("Enter 10 character ISBN number (Do Not Separate ISBN Characters With"
          "Spaces): \n\n");

   for(i=0; i<=10; i++)
      a[i]=getchar();

   x=check();

   if(x==a[9])
      printf("ISBN is valid.");
   else
      printf("ISBN is invalid");


   system("PAUSE");
   return 0;
}

int check()
{
   int sum,
       x,
       y=0;

   for(i=0; i<=9; i++)
      a[i]=a[i]-48;
   for(i=0; i<=9; i++)
   {
      x=y+(i+1)*a[i];
      y=x;
   }
   sum=x%11;
   return sum;
}

Inconsistent (or wrong) parts of the app is colored red.