Hello, as a project I am working on a player vs. computer game of Connect Four- where the computer has a lot of attitude. My code is below; the comments explain everything.
// A Player vs. Computer Connect 4 game
#include <iostream>
#include <vector>
#include <string>
#include <cstdlib>
#include <ctime>
using namespace std;
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//global constants & vars.
const char EMPTY=' ';
const char x='X';
const char o='O';
const char& X=x;
const char& O=o;
char empty=' ';
char& eRef=empty;
//GetOpposite function-needed in Computer obj.'s GetMove() member function & when assigning each obj. their own m_pieces'
int GetOpposite(const char& aPiece)
{
if (aPiece==X)
{
return O;
}
else
{
return X;
}
}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
class Board
{
friend ostream& operator<< (ostream& os, const Board& aBoard);
public:
Board();
bool GameWon(char& charRef);//
bool GameTied();//
bool IsFull();//
int GetHumanMove(); //Gives column #
void SetBoard(int& column,const char& character);
bool MoveAcceptable(int& rAns);//
void RemoveTopPiece(int& colNum);//
void ClearBoard();//
bool GameOver(char& r_PieceThatWon);
private:
int ConvertX(int* pX);
int ConvertY(int* pY);
bool ColumnCheckFull(int& column);//
char m_Array[7][6];
int m_Rows=6;
int m_Col=7;
int m_winComNum=57;
int m_Combinations[57][4]={
{1,8,15,22},{8,15,22,29},{15,22,29,36},
{2,9,16,23},{9,16,23,30},{16,23,30,37},
{3,10,17,24},{10,17,24,31},{17,24,31,38},
{4,11,18,25},{11,18,25,32},{18,25,32,39},
{5,12,19,26},{12,19,26,33},{19,26,33,40},
{6,13,20,27},{13,20,27,34},{20,27,34,41},
{7,14,21,28},{14,21,28,35},{21,28,35,42}, //finished with vertical combinations (21)
{1,2,3,4},{2,3,4,5},{3,4,5,6},{4,5,6,7},
{8,9,10,11},{9,10,11,12},{10,11,12,13},{11,12,13,14},
{15,16,17,18},{16,17,18,19},{17,18,19,20},{18,19,20,21},
{22,23,24,25},{23,24,25,26},{24,25,26,27},{25,26,27,28},
{29,30,31,32},{30,31,32,33},{31,32,33,34},{32,33,34,35},
{36,37,38,39},{37,38,39,40},{38,39,40,41},{39,40,41,42}, //finished with horizontal combinations(24)
{4,10,16,22},{5,11,17,23},{11,17,23,29},{6,12,18,24},{12,18,24,30},{18,24,30,36},
{7,13,19,25},{13,19,25,31},{19,25,31,37},{14,20,26,32},{20,26,32,38},{21,27,33,39}}; //finished with diagonal combinations (12)
};
bool Board::GameOver(char& r_PieceThatWon)
{
//check for tie
if (GameTied())
{
return true;
}
else if (GameWon(r_PieceThatWon))
{
return true;
}
else
{
return false;
}
}
Board::Board()
{
for (int i=0; i<7;++i)
{
for (int v=0;v<6;++v)
{
m_Array[i][v]=EMPTY;
}
}
}
bool Board::GameWon(char& charRef)
{
//Checks if the game has been won
//Check possible combinations
//character reference is modified to show type of piece that won the game
bool truth=false;
int NumbersComb[4];
int indexXY[4][2];
int* pNum;
for (int i=0;i<m_winComNum;++i)
{
//convert numbers to column and row#'s for indexing
for (int v=0;v <4;++v)
{
NumbersComb[v]=m_Combinations[i][v];
}
//got combination's four numbers in list-convert
for (int i=0;i<4;++i)
{
//get number
pNum=&(NumbersComb[i]);
//convert x & y
for (int v=0;v<2;++v)
{
if (v==0)
{
indexXY[i][v]=ConvertX(pNum); //convert X
}
else
{
indexXY[i][v]=ConvertY(pNum); //convert y
}
}
}
//check for winning combo
if ((m_Array[indexXY[0][0]][indexXY[0][1]]!=EMPTY)&& (m_Array[indexXY[0][0]][indexXY[0][1]]==
m_Array[indexXY[1][0]][indexXY[1][1]]==
m_Array[indexXY[2][0]][indexXY[2][1]]==
m_Array[indexXY[3][0]][indexXY[3][1]]))
{
truth=true;
charRef=m_Array[indexXY[0][0]][indexXY[0][1]];
break;
}
}
return truth;
}
int Board::ConvertX(int* pX)
{
int xCoord;
xCoord=((*pX)%7)-1;
if (xCoord==-1)
{
xCoord=6;
}
return xCoord;
}
int Board::ConvertY(int* pY)
{
int yC;
if (*pY<=7)
{
yC=0;
}
else if (*pY<=14)
{
yC=1;
}
else if (*pY<=21)
{
yC=2;
}
else if (*pY<=28)
{
yC=3;
}
else if (*pY<=35)
{
yC=4;
}
else
{
yC=5;
}
return yC;
}
bool Board::IsFull()
{
bool truth=true;
for (int i=0;i<7;++i)
{
for (int v = 0;v<6;++v)
{
if (m_Array[i][v]==EMPTY)
{
truth=false;
break;
}
}
if (truth==false)
{
break;
}
}
return truth;
}
bool Board::GameTied()
{
bool tied=false;
if (((GameWon(eRef)==false)&&(IsFull()==true)))
{
tied=true;
}
return tied;
}
int Board::GetHumanMove() //gives column number (1-7)
{
int ans = 0;
cout << "\n\nWhat column will you place your piece? (1-7): ";
cin>>ans;
cout << endl;
while ((MoveAcceptable(ans)==false)||(ans<1)||(ans>7))
{
cout << "That is an illegal move, foolish human. Use your inefficient brains to make a better decision."<<endl;
cout << "My Silicon processor is better than yours, and inexpensive too..."<<endl;
cout << "What column will you place your piece? (1-7): ";
cin>>ans;
cout << endl;
}
cout << "Fine..."<<endl;
return ans;
}
bool Board::MoveAcceptable(int& rAns)
{
if (!rAns==0)
{
bool acceptable=true;
//check for full column
if (ColumnCheckFull(rAns)==false)
{
acceptable=false;
}
return acceptable;
}
else
{
return false;
}
}
bool Board::ColumnCheckFull(int &column)
{
//check for full column
bool acceptable=false;
int row=5;//1st row-move to bottom (6th)
int concreteStartIndex=row; //1st row number
//check if the column is full-rotate upwards
for (int i=0;i<6;++i)
{
if (m_Array[column][concreteStartIndex]==EMPTY)
{
acceptable=true;
break;
}
concreteStartIndex-=1;
}
return acceptable;
}
void Board::SetBoard(int& column,const char& character)
{
//parameter is a valid column number: drop piece all the way down (as far as possible) and change the character (with index)
//column number is limited: 1-7
//create a duplicate variable and drop the index down 5 rows
const int colInd=column-1;
int index=5;
//check, and if needed start looping backwards up the rows
if (m_Array[colInd][index]==EMPTY)
{
m_Array[colInd][index]=character;
}
else
{
while (index >= 0)
{
index-=1;
//check for empty characters
if (m_Array[colInd][index]==EMPTY)
{
m_Array[colInd][index]=character;
break;
}
}
}
}
void Board::RemoveTopPiece(int& colNum)
{
//check if column has at least one piece
int colInd=colNum;
colInd-=1;
int breakOffPoint;
int colEmpty=true;
//rotate through column and check for empty
for (int i=0;i<6;++i)
{
if (m_Array[colInd][i]!=EMPTY)
{
colEmpty=false;
breakOffPoint=i;
break;
}
}
//if column isn't empty, change breakOffPoint term back to EMPTY
if (colEmpty==false)
{
m_Array[colInd][breakOffPoint]=EMPTY;
}
}
void Board::ClearBoard()
{
//removes all pieces-game is restarted for new round
for (int i=0; i<7;++i)
{
for (int v=0;v<6;++v)
{
m_Array[i][v]=EMPTY;
}
}
}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
class GenericPlayer
{
public:
GenericPlayer(Board& aBoard,const string& aName,const char& piece);
virtual string GetName()=0;
virtual int GetMove()=0;
void SetPiece(const char& piece);
inline char GetPiece();
string m_Name;
char m_Piece;
Board m_Board;
};
GenericPlayer::GenericPlayer( Board& aBoard,const string& aName,const char& piece)
{
m_Board=aBoard;
m_Name=aName;
m_Piece=piece;
}
void GenericPlayer::SetPiece(const char& piece)
{
m_Piece=piece;
}
char GenericPlayer::GetPiece()
{
return m_Piece;
}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
class Player:public GenericPlayer
{
public:
Player(Board& aBoard,const char& piece);
virtual inline string GetName();
virtual int GetMove();
bool WantToMoveFirst();
string GetNameInitially() const;
};
Player::Player(Board& aBoard,const char& piece):
GenericPlayer(aBoard,GetNameInitially(),piece)
{}
string Player::GetNameInitially() const
{
string ans;
cout << "What's your name?: ";
cin>>ans;
cout << endl;
return ans;
}
inline string Player::GetName()
{
return m_Name;
}
int Player::GetMove()
{
int move=m_Board.GetHumanMove();
return move;
}
bool Player::WantToMoveFirst()
{
char goFirst;
cout << "\nDo you require the first move? (y/n): ";
cin>>goFirst;
goFirst=toupper(goFirst);
cout <<endl;
while ((goFirst!='N')&&(goFirst!='Y'))
{
cout << "\nYour answer was invalid- <Enter> either 'y' or 'n' for 'Yes' or 'No'"<<endl;
cout << "\nDo you require the first move? (y/n): ";
cin>>goFirst;
goFirst=toupper(goFirst);
cout <<endl;
}
if (goFirst == 'Y')
{
cout << "\nThen take the first move. You will need it.\n";
}
else
{
cout << "\nYour bravery will be your undoing...I will go first.\n";
}
return (goFirst=='Y');
}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
class Computer: public GenericPlayer
{
public:
Computer(Board& aBoard, const char& piece);
void GreetOpponent();
void ReactToWin(Player& human,const char& hPiece,const char& wPiece);
virtual int GetMove();
virtual inline string GetName();
};
string Computer::GetName()
{
return "Macintosh";
}
Computer::Computer(Board& aBoard, const char& piece):
GenericPlayer(aBoard,"Macintosh",piece)
{
//Seed random number generator for its random number selections
srand(static_cast<unsigned int>(time(0))); //seeded number generator
}
void Computer::GreetOpponent()
{
cout << "\nWelcome to the ultimate man vs. machine showdown: Connect Four."<<endl;
cout << "-where human brain is pit against my silicon processor"<<endl;
cout << "\n\n\nMake your move known by entering a number, 1-7. The number"<<endl;
cout << "corresponds to the desired column for placing your piece, as illustrated:"<<endl;
cout << "\n\t\t 1 2 3 4 5 6 7"<<endl;
cout << m_Board;
cout << "\n\nPrepare yourself, human. The ultimate battle is about to begin."<<endl;
}
int Computer::GetMove()
{
//Using AI, plot next move. Priorities: 1-If Computer can win, place piece. 2-If Commputer can block human, place piece,
//3- Make best move avaliable
int move=0;
int i=0;
int& rI=i;
bool found=false;
//Check for computer winning
for (i=1;i<8;++i)
{
//rotate through possible column numbers. If move is acceptable and computer can win-save that and break
if (m_Board.MoveAcceptable(rI))
{
//set board to num
m_Board.SetBoard(rI, m_Piece);
//if computer wins game- save move & remove that from board (just for time being)
if (m_Board.GameWon(eRef))
{
move=rI;
m_Board.RemoveTopPiece(rI);
found=true;
break;
}
}
}
//if the computer can't win on next move- block player from winning
if (!found)
{
const char humanPiece=GetOpposite(m_Piece);
//rotate through the column numbers
for (i=1;i<8;++i)
{
//rotate through possible column numbers. If move is acceptable and human can win-save that and break
if (m_Board.MoveAcceptable(rI))
{
//set board to num
m_Board.SetBoard(rI, humanPiece);
//if human wins game- save move & remove that from board (just for time being)
if (m_Board.GameWon(eRef))
{
move=rI;
m_Board.RemoveTopPiece(rI);
found=true;
break;
}
}
}
}
if (!found)
{
//it the computer can't win or block- randomly select a move using random number generator
//first, get a random number (1-7)
int rNum=(rand()%7)+1;
int& r_num=rNum;
while (!m_Board.MoveAcceptable(r_num))
{
rNum=(rand()%7)+1;
r_num=rNum; //keep generating a random column number until move is acceptable
}
move=r_num;
}
cout << "I shall put my piece in column "<<move<<endl;
return move;
}
void Computer::ReactToWin(Player& human,const char& hPiece,const char& wPiece)
{
/*Game is over and the computer is expected to have an appropriate reaction per each of the game's outcomes:
1- it wins, 2- human wins, 3- both are tied.*/
if (wPiece==m_Piece)
{
cout<< "I, the "<<m_Name<< " won!\n";
cout << "As I predicted, human, I am triumphant once more -- proof\n";
cout << "that computers are superior to humans in all regards.\n";
}
else if (wPiece==hPiece)
{
cout << human.GetName() << "'s won!\n";
cout << "No, no! It cannot be! Somehow you tricked me, human.\n";
cout << "But never again! I, the "<< m_Name<<", so swear it!\n";
}
else
{
cout << "It's a tie!\n";
cout << "You were most lucky, human, and somehow managed to tie me.\n";
cout << "Celebrate...for this is the best you will ever achieve.\n";
}
}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
class ConnectFourGame
{
public:
ConnectFourGame(Board& aBoard,Player& aPlayer,Computer& aComputer);//
bool PlayerWantToPlay();//
void ClearMembers();//
void PlayGames();//
void PlayOneRound();
char GetPlayerPieceChoice();
bool FirstRound;
bool playerWantToGoFirst;
static char PieceThatWon;
Board m_Board;
Player m_Player;
Computer m_Computer;
};
ConnectFourGame::ConnectFourGame(Board& aBoard,Player& aPlayer,Computer& aComputer):
m_Board(aBoard),m_Player(aPlayer),m_Computer(aComputer),FirstRound(true),playerWantToGoFirst(false)
{
PieceThatWon=empty;
}
bool ConnectFourGame::PlayerWantToPlay()
{
char ans;
cout << "\n\n\nDo you want to play another game? (y/n): ";
cin >> ans;
cout << "\n\n";
ans =toupper(ans);
while (ans != 'N'||ans!='Y')
{
cout << "Your answer is limited to either 'y' or 'n'";
cout << "\nDo you want to play another game? (y/n): ";
cin >> ans;
cout << "\n\n";
ans =toupper(ans);
}
return (ans =='N');
}
void ConnectFourGame::ClearMembers()
{
if (!FirstRound)
{
m_Board.ClearBoard();
FirstRound=false;
}
//Get Player Char
playerWantToGoFirst=m_Player.WantToMoveFirst();
if (playerWantToGoFirst)
{
m_Player.SetPiece(X);
m_Computer.SetPiece(O);
}
else
{
m_Computer.SetPiece(O);
m_Player.SetPiece(X);
}
}
void ConnectFourGame::PlayGames()
{
m_Computer.GreetOpponent();
//start looping using a do-while loop through multiple rounds of games
do
{
PlayOneRound();
} while (PlayerWantToPlay()==true);
cout << "\n\nOkay then- Bye!"<<endl;
}
void ConnectFourGame::PlayOneRound()
{
//Get if player wants to move first
int turn;
int move;
ClearMembers();
if (playerWantToGoFirst)
{
turn=0;
}
else
{
turn =1;
}
while (!m_Board.GameOver(PieceThatWon)) //If a player of the game won- the character is saved in a static var.
{
//While not game won- play: 0-human first, 1-computer first
cout << "\n\n"<<m_Board;
if (turn==0)
{
move=m_Player.GetMove();
m_Board.SetBoard(move, m_Player.GetPiece());
turn=1;
}
else
{
move=m_Computer.GetMove();
m_Board.SetBoard(move, m_Computer.GetPiece());
turn=0;
}
cout << "\n\nHere is the result of the move:\n"<<m_Board<<endl;
}
//game over-have computer react and declare the game's outcome
m_Computer.ReactToWin(m_Player, m_Player.GetPiece(), PieceThatWon);
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//overloading << operator so a board obj. can be sent to cout
ostream& operator<< (ostream& os, const Board& aBoard)
{
os << "\t\t+---+---+---+---+---+---+---+"<<endl;
for (int i=0;i<6;++i)
{
os << "\t\t| "<<aBoard.m_Array[0][i]<<" | "<<aBoard.m_Array[1][i]<<" | "<<aBoard.m_Array[2][i]<<" | "<<aBoard.m_Array[3][i]<<" | "<<aBoard.m_Array[4][i]<<" | "<<aBoard.m_Array[5][i]<<" | "<<aBoard.m_Array[6][i]<<" | "<<endl;
os << "\t\t|---+---+---+---+---+---+---|"<<endl;
}
os<< "\t\t| |"<<endl;
return os;
}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
int main()
{
Board theGameBoard;
Board& r_Board=theGameBoard;
Player aPlayer(r_Board,X); //by default-let Player have 'X' piece
Player& r_Player=aPlayer;
Computer aComputer(r_Board,O);//by default let computer have 'O' piece
Computer& r_Computer=aComputer;
ConnectFourGame aConnect4Game(r_Board,r_Player,r_Computer);
aConnect4Game.PlayGames();
return 0;
}
I expected for the code to compile correctly and start working, but I recieved the following two errors from my xCode C++ compiler:
First Message:
Undefined symbols for architecture x86_64:
"ConnectFourGame::PieceThatWon", referenced from:
ConnectFourGame::ConnectFourGame(Board&, Player&, Computer&) in main.o
ConnectFourGame::PlayOneRound() in main.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
Second Message:
Undefined symbols for architecture x86_64:
"ConnectFourGame::PieceThatWon", referenced from:
ConnectFourGame::ConnectFourGame(Board&, Player&, Computer&) in main.o
ConnectFourGame::PlayOneRound() in main.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
Being a beginner student with C++ and unfamiliar with the xCode compiler, I have no idea what is causing the problem. Could any of you offer any advice on how to fix this problem?
Thanks!
