#include <iostream.h>
#include <stdlib.h>

void print_hex_digit(int x)
{
  switch(x) {
  case 0: cout << "0"; break;
  case 1: cout << "1"; break;
  case 2: cout << "2"; break;
  case 3: cout << "3"; break;
  case 4: cout << "4"; break;
  case 5: cout << "5"; break;
  case 6: cout << "6"; break;
  case 7: cout << "7"; break;
  case 8: cout << "8"; break;
  case 9: cout << "9"; break;
  case 10: cout << "A"; break;
  case 11: cout << "B"; break;
  case 12: cout << "C"; break;
  case 13: cout << "D"; break;
  case 14: cout << "E"; break;
  case 15: cout << "F"; break;
  default:
    cout << "Error, print_hex_digit accepts 0-15 only\n";
    exit(-1);
    break;
  }
}