#include <stdio.h>
#include <limits.h>

typedef unsigned char byte;

void show_bytes(void * start, size_t len){

  printf("%lu bytes from %p:", len, start);

  int i;
  for(i = 0; i < len; i++){
    printf(" %.2x", ((byte *) start)[i]);
  }
  printf("\n");

}

void unsigned_demo(){
  unsigned short us = 13;
  unsigned int ui = 13;
  unsigned long ul = 13;

  //show_bytes(&ui,4);

   printf("%hu (%lu bytes), %u (%lu bytes), %lu (%lu bytes)\n", us, sizeof(unsigned short),  ui,sizeof(unsigned int),  ul, sizeof(unsigned long));
  
  show_bytes(&us, 8);
  show_bytes(&ui, 8);
  show_bytes(&ul, 8);

  unsigned short us2 = (unsigned short) ui;
  unsigned short us3 = (unsigned short) ul;
  unsigned int ui2 = (unsigned int) us;
  unsigned int ui3 = (unsigned int) ul;
  unsigned long ul2 = (unsigned long) us;
  unsigned long ul3 = (unsigned long) ui;
  printf("%hu, %hu, %u, %u, %lu, %lu\n", us2, us3, ui2, ui3, ul2, ul3);

  unsigned long ul4 = (unsigned long) INT_MAX*10;
  unsigned int ui4 = (unsigned int) ul4;
  unsigned short us4 = (unsigned short) ul4;
  printf("%lu, %u, %hu\n", ul4, ui4, us4);

  show_bytes(&ul4, 8);
  show_bytes(&ui4, 4);
  show_bytes(&us4, 2);
}

void signed_demo(){
  int x = -65536;
  short s = (short) x;
  long l = (long) x;
  printf("%hi, %d, %ld\n", s, x, l);
  show_bytes(&s, 2);
  show_bytes(&x, 4);
  show_bytes(&l, 8);

  unsigned int y = (unsigned int) x;
  int z = (int) y;

  printf("%d, %u, %d\n", x, y, z);
  show_bytes(&x, 4);
  show_bytes(&y, 4);
  show_bytes(&z, 4);
}

int main()
{
  printf("Unsigned int demo:\n");
  unsigned_demo();

  printf("\nSigned int demo:\n");
  signed_demo();

  return 0;
}