Beginning C++ Through Gam…rogramming (2nd Edition)/BCGP2E.ISO/source/chapter10/blackjack.cpp

C/C++ Source or Header | 2006-11-02 | 11.0 KB | 494 lines

//Blackjack
//Plays a simple version of the casino game of blackjack; for 1 - 7 players

#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <ctime>

using namespace std;

class Card
{
public:
    enum rank {ACE = 1, TWO, THREE, FOUR, FIVE, SIX, SEVEN, EIGHT, NINE, TEN,
               JACK, QUEEN, KING};
    enum suit {CLUBS, DIAMONDS, HEARTS, SPADES};

    //overloading << operator so can send Card object to standard output
    friend ostream& operator<<(ostream& os, const Card& aCard);

    Card(rank r = ACE, suit s = SPADES, bool ifu = true);

    //returns the value of a card, 1 - 11
    int GetValue() const;

    //flips a card; if face up, becomes face down and vice versa
    void Flip();

private:
    rank m_Rank;
    suit m_Suit;
    bool m_IsFaceUp;
};

Card::Card(rank r, suit s, bool ifu):  m_Rank(r), m_Suit(s), m_IsFaceUp(ifu)
{}

int Card::GetValue() const
{
    //if a cards is face down, its value is 0
    int value = 0;
    if (m_IsFaceUp)
    {
        //value is number showing on card
        value = m_Rank;
        //value is 10 for face cards
        if (value > 10)
            value = 10;
    }
    return value;
}

void Card::Flip()
{
    m_IsFaceUp = !(m_IsFaceUp);
}

class Hand
{
public:
    Hand();

    virtual ~Hand();

    //adds a card to the hand
    void Add(Card* pCard);

    //clears hand of all cards
    void Clear();

    //gets hand total value, intelligently treats aces as 1 or 11
    int GetTotal() const;

protected:
    vector<Card*> m_Cards;
};

Hand::Hand()
{
    m_Cards.reserve(7);
}

Hand::~Hand()
{
    Clear();
}

void Hand::Add(Card* pCard)
{
    m_Cards.push_back(pCard);
}

void Hand::Clear()
{
    //iterate through vector, freeing all memory on the heap
    vector<Card*>::iterator iter = m_Cards.begin();
    for (iter = m_Cards.begin(); iter != m_Cards.end(); ++iter)
    {
        delete *iter;
        *iter = 0;
    }
    //clear vector of pointers
    m_Cards.clear();
}

int Hand::GetTotal() const
{
    //if no cards in hand, return 0
    if (m_Cards.empty())
        return 0;

    //if a first card has value of 0, then card is face down; return 0
    if (m_Cards[0]->GetValue() == 0)
        return 0;

    //add up card values, treat each Ace as 1
    int total = 0;
    vector<Card*>::const_iterator iter;
    for (iter = m_Cards.begin(); iter != m_Cards.end(); ++iter)
        total += (*iter)->GetValue();

    //determine if hand contains an Ace
    bool containsAce = false;
    for (iter = m_Cards.begin(); iter != m_Cards.end(); ++iter)
        if ((*iter)->GetValue() == Card::ACE)
            containsAce = true;

    //if hand contains Ace and total is low enough, treat Ace as 11
    if (containsAce && total <= 11)
        //add only 10 since we've already added 1 for the Ace
        total += 10;

    return total;
}

class GenericPlayer : public Hand
{
    friend ostream& operator<<(ostream& os, const GenericPlayer& aGenericPlayer);

public:
    GenericPlayer(const string& name = "");

    virtual ~GenericPlayer();

    //indicates whether or not generic player wants to keep hitting
    virtual bool IsHitting() const = 0;

    //returns whether generic player has busted - has a total greater than 21
    bool IsBusted() const;

    //announces that the generic player busts
    void Bust() const;

protected:
    string m_Name;
};

GenericPlayer::GenericPlayer(const string& name):
    m_Name(name)
{}

GenericPlayer::~GenericPlayer()
{}

bool GenericPlayer::IsBusted() const
{
    return (GetTotal() > 21);
}

void GenericPlayer::Bust() const
{
    cout << m_Name << " busts.\n";
}

class Player : public GenericPlayer
{
public:
    Player(const string& name = "");

    virtual ~Player();

    //returns whether or not the player wants another hit
    virtual bool IsHitting() const;

    //announces that the player wins
    void Win() const;

    //announces that the player loses
    void Lose() const;

    //announces that the player pushes
    void Push() const;
};

Player::Player(const string& name):
    GenericPlayer(name)
{}

Player::~Player()
{}

bool Player::IsHitting() const
{
    cout << m_Name << ", do you want a hit? (Y/N): ";
    char response;
    cin >> response;
    return (response == 'y' || response == 'Y');
}

void Player::Win() const
{
    cout << m_Name <<  " wins.\n";
}

void Player::Lose() const
{
    cout << m_Name <<  " loses.\n";
}

void Player::Push() const
{
    cout << m_Name <<  " pushes.\n";
}

class House : public GenericPlayer
{
public:
    House(const string& name = "House");

    virtual ~House();

    //indicates whether house is hitting - will always hit on 16 or less
    virtual bool IsHitting() const;

    //flips over first card
    void FlipFirstCard();
};

House::House(const string& name):
    GenericPlayer(name)
{}

House::~House()
{}

bool House::IsHitting() const
{
    return (GetTotal() <= 16);
}

void House::FlipFirstCard()
{
    if (!(m_Cards.empty()))
        m_Cards[0]->Flip();
    else cout << "No card to flip!\n";
}

class Deck : public Hand
{
public:
    Deck();

    virtual ~Deck();

    //create a standard deck of 52 cards
    void Populate();

    //shuffle cards
    void Shuffle();

    //deal one card to a hand
    void Deal(Hand& aHand);

    //give additional cards to a generic player
    void AdditionalCards(GenericPlayer& aGenericPlayer);
};

Deck::Deck()
{
    m_Cards.reserve(52);
    Populate();
}

Deck::~Deck()
{}

void Deck::Populate()
{
    Clear();
    //create standard deck
    for (int s = Card::CLUBS; s <= Card::SPADES; ++s)
            for (int r = Card::ACE; r <= Card::KING; ++r)
                Add(new Card(static_cast<Card::rank>(r), static_cast<Card::suit>(s)));
}

void Deck::Shuffle()
{
    random_shuffle(m_Cards.begin(), m_Cards.end());
}

void Deck::Deal(Hand& aHand)
{
    if (!m_Cards.empty())
    {
        aHand.Add(m_Cards.back());
        m_Cards.pop_back();
    }
    else
    {
        cout << "Out of cards. Unable to deal.";
    }
}

void Deck::AdditionalCards(GenericPlayer& aGenericPlayer)
{
    cout << endl;
    //continue to deal a card as long as generic player isn't busted and
    //wants another hit
    while ( !(aGenericPlayer.IsBusted()) && aGenericPlayer.IsHitting() )
    {
        Deal(aGenericPlayer);
        cout << aGenericPlayer << endl;

        if (aGenericPlayer.IsBusted())
            aGenericPlayer.Bust();
    }
}

class Game
{
public:
    Game(const vector<string>& names);

    ~Game();

    //plays the game of blackjack
    void Play();

private:
    Deck m_Deck;
    House m_House;
    vector<Player> m_Players;
};

Game::Game(const vector<string>& names)
{
    //create a vector of players from a vector of names
    vector<string>::const_iterator pName;
    for (pName = names.begin(); pName != names.end(); ++pName)
        m_Players.push_back(Player(*pName));

    srand(time(0));    //seed the random number generator
    m_Deck.Populate();
    m_Deck.Shuffle();
}

Game::~Game()
{}

void Game::Play()
{
    //deal initial 2 cards to everyone
    vector<Player>::iterator pPlayer;
    for (int i = 0; i < 2; ++i)
    {
        for (pPlayer = m_Players.begin(); pPlayer != m_Players.end(); ++pPlayer)
            m_Deck.Deal(*pPlayer);
        m_Deck.Deal(m_House);
    }

    //hide house's first card
    m_House.FlipFirstCard();

    //display everyone's hand
    for (pPlayer = m_Players.begin(); pPlayer != m_Players.end(); ++pPlayer)
        cout << *pPlayer << endl;
    cout << m_House << endl;

    //deal additional cards to players
    for (pPlayer = m_Players.begin(); pPlayer != m_Players.end(); ++pPlayer)
        m_Deck.AdditionalCards(*pPlayer);

    //reveal house's first card
    m_House.FlipFirstCard();
    cout << endl << m_House;

    //deal additional cards to house
    m_Deck.AdditionalCards(m_House);

    if (m_House.IsBusted())
    {
        //everyone still playing wins
        for (pPlayer = m_Players.begin(); pPlayer != m_Players.end(); ++pPlayer)
            if ( !(pPlayer->IsBusted()) )
                pPlayer->Win();
    }
    else
    {
         //compare each player still playing to house
        for (pPlayer = m_Players.begin(); pPlayer != m_Players.end(); ++pPlayer)
            if ( !(pPlayer->IsBusted()) )
            {
                if (pPlayer->GetTotal() > m_House.GetTotal())
                    pPlayer->Win();
                else if (pPlayer->GetTotal() < m_House.GetTotal())
                    pPlayer->Lose();
                else
                    pPlayer->Push();
            }
    }

    //remove everyone's cards
    for (pPlayer = m_Players.begin(); pPlayer != m_Players.end(); ++pPlayer)
        pPlayer->Clear();
    m_House.Clear();
}

//function prototypes
ostream& operator<<(ostream& os, const Card& aCard);
ostream& operator<<(ostream& os, const GenericPlayer& aGenericPlayer);

int main()
{
    cout << "\t\tWelcome to Blackjack!\n\n";

    int numPlayers = 0;
    while (numPlayers < 1 || numPlayers > 7)
    {
        cout << "How many players? (1 - 7): ";
        cin >> numPlayers;
    }

    vector<string> names;
    string name;
    for (int i = 0; i < numPlayers; ++i)
    {
        cout << "Enter player name: ";
        cin >> name;
        names.push_back(name);
    }
    cout << endl;

    //the game loop
    Game aGame(names);
    char again = 'y';
    while (again != 'n' && again != 'N')
    {
        aGame.Play();
        cout << "\nDo you want to play again? (Y/N): ";
        cin >> again;
    }

    return 0;
}

//overloads << operator so Card object can be sent to cout
ostream& operator<<(ostream& os, const Card& aCard)
{
    const string RANKS[] = {"0", "A", "2", "3", "4", "5", "6", "7", "8", "9",
                            "10", "J", "Q", "K"};
    const string SUITS[] = {"c", "d", "h", "s"};

    if (aCard.m_IsFaceUp)
        os << RANKS[aCard.m_Rank] << SUITS[aCard.m_Suit];
    else
        os << "XX";

    return os;
}

//overloads << operator so a GenericPlayer object can be sent to cout
ostream& operator<<(ostream& os, const GenericPlayer& aGenericPlayer)
{
    os << aGenericPlayer.m_Name << ":\t";

    vector<Card*>::const_iterator pCard;
    if (!aGenericPlayer.m_Cards.empty())
    {
        for (pCard = aGenericPlayer.m_Cards.begin();
             pCard != aGenericPlayer.m_Cards.end(); ++pCard)
            os << *(*pCard) << "\t";

        if (aGenericPlayer.GetTotal() != 0)
            cout << "(" << aGenericPlayer.GetTotal() << ")";
    }
    else
    {
        os << "<empty>";
    }

    return os;
}