arrays 1

[welshspoon]

hi
i'm writing a program so that a user can enter a sequence of values at the command prompt which are then manipulated. These values are stored in an array of size 1000.
The problem im having is that I want the program to stop asking the user for values once a zero has been entered and then proceed to manipulate the entered values.

I've written the same thing in Java and that works fine but as I'm new to C i'm not sure what to do.

Thanks in advance for your help

 

[DaveSinkula]

#include <stdio.h>

int array[1000];

int main(void)
{
   size_t count, i = 0;
   while ( i < sizeof array / sizeof *array )
   {
      int value;
      printf("Enter value #%lu: ", (long unsigned)(i + 1));
      fflush(stdout);
      if ( scanf("%d", &value) == 1 )
      {
         if ( value == 0 )
         {
            break;
         }
         array[i++] = value;
      }
   }
   for ( count = i, i = 0; i < count; ++i )
   {
      printf("array[%lu] = %d\n", (long unsigned)i, array[i]);
   }
   return 0;
}

/* my output
Enter value #1: 9
Enter value #2: 16
Enter value #3: 42
Enter value #4: 0
array[0] = 9
array[1] = 16
array[2] = 42
*/

 

[lionelhill]

Another way to do this, which works even in languages without "break" (e.g. the late lamented pascal) is to use code exactly as DaveSinkula, but when value==0, set i to sizeof array. This stops the loop next time round. The downside is that i is no longer a measure of how many numbers were entered, so you either have to use another variable for that, or you have to look for the zero when you're processing the array.