I am trying to use a dynamically allocate an array using a pointer in my tic tac toe game. I am a little confused on how exactly pointers work. We are using the cplusplus.com website as our textbook, and I think the section on pointers is a little confusing for me. Would it be possible to get a explanation of it and possibly help do that to my tic tac toe game? Here is my code:
//Sophia Ali
// TicTacToe (CS-509 Assignment 5)
#include<iostream>
#include<cstdlib>
using namespace std;
enum Status { WIN, DRAW, CONTINUE, QUIT };
void showBoard( const char board[], int boardSize );
// show current state of board
Status checkGameState( const char board[] );
// returns WIN or CONTINUE
int getHumanSquare( const char board[] );
int getComputerSquare( const char board[] );
bool checkBadSquare( const char board[], int squareNum );
// checks to see if a chosen square is already taken; returns true if
// already taken; used by get*Square functions above.
int getrandint( int min, int max );
int main()
{
char board[] = "123456789"; // 10 element char board
const int boardSize = 10;
Status gameState = CONTINUE;
int gametype, squareChoice, turnNum = 0;
char currentSymbol; // 'o' or 'x'
cout << "\n This is a Tic Tac Toe program. Choose the type of game: "
<< "\n (1) human o vs. human x (2) human o vs. dumb computer x"
<< "\n\n -> ";
cin >> gametype;
/* Show the current state of Tic Tac Toe board. */
showBoard( board, boardSize );
/*
Main game loop
*/
while ( gameState == CONTINUE )
{
/* Increment turnNum by 1. */
turnNum++;
/* If turnNum equal to 10
Set gameState to DRAW.
Break out of while loop. */
if ( turnNum == 10 )
{
gameState = DRAW;
break;
}
/* If we are on an odd-numbered turn
Print "It's o's turn."
Set currentSymbol to 'o'.
Call getHumanSquare function to get squareChoice.
Else (we are on an even-numbered turn)
Print "It's x's turn."
Set currentSymbol to 'x'.
If the gametype is 1 (human vs. human)
Call getHumanSquare function to get squareChoice.
Else (gametype is 2 (human vs. computer))
Call getComputerSquare function to get squareChoice.*/
// Get current player's square choice and insert into board
if ( turnNum%2 != 0)
{
cout << "\n It's o's turn.";
currentSymbol = 'o';
squareChoice = getHumanSquare( board );
}
else
{
cout << "\n It's x's turn.";
currentSymbol = 'x';
if ( gametype == 1 )
squareChoice = getHumanSquare( board );
else
squareChoice = getComputerSquare( board );
}
/* If squareChoice is -1 (human player quit)
Set gameState to QUIT.
Else
Insert currentSymbol into board at (squareChoice - 1).
Show the current state of the Tic Tac Toe board.
Call checkGameState function to determine the gameState. */
if ( squareChoice == -1 )
gameState = QUIT;
else
{
board[ squareChoice - 1 ] = currentSymbol;
showBoard( board, boardSize );
gameState = checkGameState( board );
}
} // end while
/* If gameState is WIN
print "Player " currentSymbol " is the winner." */
/* If gameState is DRAW
print "It's a draw." */
if ( gameState == WIN )
cout << "Player " <<currentSymbol << " is the winner.";
if ( gameState == DRAW )
cout << "It's a draw.";
return 0;
} // end main
/////////////////////////////////////////////////////////////////////
void showBoard( const char board [], int size )
{
cout << endl;
for ( int i = 0; i < size ; i++ )
{
cout << board[ i ] << " ";
if ( ( i + 1 ) % 3 == 0 )
cout << endl;
}
cout << endl;
}
/////////////////////////////////////////////////////////////////////
Status checkGameState( const char board[] )
{
// Board Array
//
// 1 2 3 0 1 2
// 4 5 6 --> 3 4 5
// 7 8 9 6 7 8
//
// Diagonal winners
if ( board[ 0 ] == board[ 4 ] && board[ 0 ] == board[ 8 ] )
return WIN;
else if ( board[ 2 ] == board[ 4 ] && board[ 4 ] == board[ 6 ] )
return WIN;
// Horizontal winners
else if ( board[ 0 ] == board[ 1 ] && board[ 1 ] == board[ 2 ] )
return WIN;
else if ( board[ 3 ] == board[ 4 ] && board[ 4 ] == board[ 5 ] )
return WIN;
else if ( board[ 6 ] == board[ 7 ] && board[ 7 ] == board[ 8 ] )
return WIN;
// Vertical winners
else if ( board[ 0 ] == board[ 3 ] && board[ 3 ] == board[ 6 ] )
return WIN;
else if ( board[ 1 ] == board[ 4 ] && board[ 4 ] == board[ 7 ] )
return WIN;
else if ( board[ 2 ] == board[ 5 ] && board[ 5 ] == board[ 8 ] )
return WIN;
else
return CONTINUE;
}
/////////////////////////////////////////////////////////////////////
int getHumanSquare( const char board[] )
{
int squareNum;
cout << "\n Input the number of an empty square: (-1 to quit) ";
cin >> squareNum;
while ( checkBadSquare( board, squareNum ) == true )
{
cout << "\n Bad input. Choose another square: ";
cin >> squareNum;
}
return squareNum;
}
/////////////////////////////////////////////////////////////////////
int getComputerSquare( const char board[] )
{
int squareNum;
squareNum = getrandint( 1, 9 );
while ( checkBadSquare( board, squareNum ) == true )
{
squareNum = getrandint( 1, 9 );
}
return squareNum;
}
/////////////////////////////////////////////////////////////////////
bool checkBadSquare( const char board[], int squareNum )
{
int realSquareNum = squareNum - 1; // count from 0
if ( squareNum == -1 )
return false; // Let quit code pass as a valid square
else if ( squareNum > 9 )
return true; // Square numbers out of range are invalid
else if ( board[ realSquareNum ] == 'o' || board[ realSquareNum ] == 'x' )
return true; // Occupied squares are invalid
else
return false; // Valid square number
}
/////////////////////////////////////////////////////////////////////
int getrandint( int min, int max )
{
int scale, shift;
scale = max - min + 1;
shift = min;
return rand() % scale + shift;
}
