#include <stdio.h>

union real_to_hex
{
      float real;
      unsigned long hex;
};

int main()
{
   union real_to_hex num;

   printf("Enter a real number (0 to quit): ");
   scanf(" %f", &num.real );
   while ( num.real != 0.0 )
   {
      printf("Internal representation: %08lx\n", num.hex );
      printf("Enter a real number (0 to quit): ");
      scanf("%f", &num.real );
   }
}