Article Writing

void main( void )
{
   /* Call with 3 integers (-1 is used as terminator). */
   printf( "Average is: %d\n", average( 2, 3, 4, -1 ) );
 
   /* Call with 4 integers. */
   printf( "Average is: %d\n", average( 5, 7, 9, 11, -1 ) );
 
   /* Call with just -1 terminator. */
   printf( "Average is: %d\n", average( -1 ) );
}

int average( int first, ... )
{
   int count = 0, sum = 0, i = first;
   va_list marker;
 
   va_start( marker, first );     /* Initialize variable arguments. */
   while( i != -1 )
   {
      sum += i;
      count++;
      i = va_arg( marker, int);
   }
   va_end( marker );              /* Reset variable arguments.      */
 
   return( sum ? (sum / count) : 0 );
}