11.9 The Best of Both Worlds

The following example is a complete program that creates a deck of cards and shuffles it. The purpose of the example is to show how the Tools.h++ template collections can be used in conjunction with the Standard C++ Library. See your Standard C++ Library documentation for more information on the features used in the example.

/* Note: This example requires the C++ Standard Library */

#include <iostream.h>
#include <algorithm>
#include <rw/tvordvec.h>

struct Card {
  char  rank;
  char  suit;

  bool operator==(const Card& c) const
    { return rank == c.rank && suit == c.suit; }

  Card() { }
  Card(char r, char s) : rank(r), suit(s) { }

  // print card: e.g. '3-C' = three of clubs, 'A-S' = ace of spades
  friend ostream& operator<<(ostream& ostr, const Card& c)
  { return (ostr << c.rank << "-" << c.suit << "  "); }
};

/*
 * A generator class - return Cards in sequence
 */
class DeckGen {
  int rankIdx;  // indexes into static arrays below
  int suitIdx;
  static const char Ranks[13];
  static const char Suits[4];
public:
  DeckGen() : rankIdx(-1), suitIdx(-1) { }

  // generate the next Card
  Card operator()() {
    rankIdx = (rankIdx + 1) % 13;
    if (rankIdx == 0)
    // cycled through ranks, move on to next suit:
      suitIdx = (suitIdx + 1) % 4;
    return Card(Ranks[rankIdx], Suits[suitIdx]);
  }
};

const char DeckGen::Suits[4]  = {'S', 'H', 'D', 'C' };
const char DeckGen::Ranks[13] = {'A', '2', '3', '4',
                                 '5', '6', '7', '8',
                                 '9', 'T', 'J', 'Q', 'K' };

int main(){
  // Tools.h++ collection:
  RWTValOrderedVector<Card> deck;
  RWTValOrderedVector<Card>::size_type pos;

  Card aceOfSpades('A','S');
  Card firstCard;

  // Use standard library algorithm to generate deck:
  generate_n(back_inserter(deck.std()), 52, DeckGen());
  cout << endl << "The deck has been created" << endl;

  // Use Tools.h++ member function to find card:
  pos = deck.index(aceOfSpades);
  cout << "The Ace of Spades is at position " << pos+1 << endl;

  // Use standard library algorithm to shuffle deck:
  random_shuffle(deck.begin(), deck.end());
  cout << endl << "The deck has been shuffled" << endl;

  // Use Tools.h++ member functions:
  pos = deck.index(aceOfSpades);
  firstCard = deck.first();

  cout << "Now the Ace of Spades is at position " << pos+1
       << endl << "and the first card is " << firstCard << endl;
}


/* Output (will vary because of the shuffle):

The deck has been created
The Ace of Spades is at position 1

The deck has been shuffled
Now the Ace of Spades is at position 37
and the first card is Q-D  

*/