/**
 * float - print out the parts of a floating point number.
 */
#include <stdio.h>
#include <stdlib.h>

int
f2i (float f)
{
  return *((int *) &f);
} // f2i

void
show_int_bits (int i)
{
  int j;
  int current;

  // For each bit position
  for (j = 31; j >= 0; j--)
    {
      // Check what the bit at position j is
      // Need the number corresponding to 00000100000000000, that is, 
      //    1 followed by j 0's
      // Can do it with expontentiation, but that's wasteful
      current = 0x1 << j;
      if ((i & current) == 0)
        printf ("0");
      else
        printf ("1");
    }
  printf ("\n");
} // show_int_bits

int
main (int argc, char **argv)
{
  float f;              // The float we wish to deconstruct
  int i;                // The digits

  // Verify parameters
  if (argc != 2)
    {
      printf ("Usage: float NUM\n");
      return EXIT_FAILURE;
    }

  // Get the number
  f = atof (argv[1]);

  // Convert to bits
  i = f2i (f);

  // Strip out anything but the exponent.
  i = i >> 23;
  i &= 255;

  // Handle special cases
  if (i == 0)
    printf ("%f is a special case (exponent 00000000)\n", f);
  else if (i == 255)
    printf ("%f is a special case (exponent 11111111)\n", f);
  else 
    printf ("For float %f, the exponent is %d\n", f, i-127);

  return EXIT_SUCCESS;
} // main