# I need help w/my tic tac toe code

S

#### sabirah

My code does not seem to be working properly...
The game is b/w a human and the computer. The computer always goes
first. The computer chooses the first corner in the first turn. in
the comp's 2nd turn, it chooses the opposite corner if possible, if
that corner is not availabe, the computer chooses randomly. In the
computers next turns...it does the following:
1. checks for a winning position
else
2. blocks human from a winning position
else
3. randomly chooses a position

The code is:

//Tic-Tac-Toe program

//
// The game board is a 3x3 array of ints
// board[3][3]:
// board[0][0] is upper left corner
// board[0][1] is top row, middle
// ...
// board[2][2] is bottom right

// 0 means the spot is empty
// 1 means 'X' has the spot
// 2 means 'O' has the spot

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

// drawpos will draw the right character to the screen, depending
// on the value of the parameter val.

// if val is 0, the spot is empty to draw a blank
// if val is 1, the spot belongs to player X, print 'X'
// if val is 2, the spot belongs to player O, print 'O'

void drawpos( int val ) {

if (val==0)
cout << " "; // val is 0, so draw a space
else if (val==1)
cout << "X"; // val is 1, so draw a 'X'
else if (val==2)
cout << "O"; // val is 2, so draw a 'O'
}

// drawrow gets an array of 3 ints and draw a
// row of a tic-tac-toe game using the array to determine
// what should go in each of the three squares.
//
// draws a row of the board

void drawrow( int row[3] ) {

cout << " "; // indent a space
drawpos(row[0]); // draw the leftmost spot
cout << " | "; // draw the vertial bar
drawpos(row[1]); // draw the middle
cout << " | "; // draw the vertial bar
drawpos(row[2]); // draw the rightmost spot
cout << endl; // newline (end of the line)
}

// drawgame will print out a tic-tac-toe game board
//
// the output looks something like this:
//
// | |
// ---|---|---
// X | | O
// ---|---|---
// X | O |
//
//
// the top left corner is board[0][0]
// the top middle is board[0][1]
// the bottom right corner is board[2][2]

void drawgame( int board[3][3] ) {

drawrow(board[0]); // draws the top row
cout << "---|---|---" << endl;
drawrow(board[1]); // draws the middlerow
cout << "---|---|---" << endl;
drawrow(board[2]); // draws the bottom row
}

bool checkPosition ( int board [3][3], int row, int col )
{

if ( ( row > 2 ) || ( row < 0 ) || ( col > 2 ) || ( col < 0 ) // out
of range test
|| ( board [ row ][ col ] != 0 ) ) //position is occupied
return false;

else return true;
}

bool won ( int board [3][3], int player )
{
int i, j;

// ROW TEST
for ( i = 0; i < 3; i++ )
{
for ( j = 0; j < 3; j++ )
if ( board [j] == player )
continue;
else
break;
if ( j == 3 )
return true;
}

// COLUMN TEST
for ( i = 0; i < 3; i++ )
{
for ( j = 0; j < 3; j++ )
if ( board [j] == player )
continue;
else
break;
if ( j == 3 )
return true;
}

//DIAGONAL TEST
if ( ( ( board[0][0] == player ) && ( board[1][1] == player ) &&
( board[2][2] == player ) ) || ( ( board[0][2] == player ) &&
( board[1][1] == player ) && ( board[2][0] == player ) ) )
return true;

return false;
}

void main ()
{
int board [3][3] = { 0, 0, 0, 0, 0, 0, 0, 0, 0 };
int turn = 1;
int flag = 0;
int row, col, player;
bool pos, testWin = 0;

drawgame ( board );

cout << "\nPlayer 1 is X............Computer is 0" << endl;
cout << "\nComputer goes first." << endl;

do
{
if ( ( turn % 2 ) == 1 ) // computer's turn
{
player = 2;
if ( turn == 1 ) // no possibility of any wins yet...choose
strategic position (CORNERS)
board[0][0] = 2;

else if ( turn == 3 ) // no possibility of any wins yet...choose
strategic position
{
if ( board[0][0] == 2 )
pos = checkPosition ( board, 2, 2 );
if ( pos )
board[2][2] = 2;

else if ( board[2][2] == 2 )
{
pos = checkPosition ( board, 0, 0 );
if ( pos )
board[0][0] = 2;

else if ( board[0][2] == 2 )
{
pos = checkPosition ( board, 2, 0 );
if ( pos )
board[2][0] = 2;

else if ( board[2][0] == 2 )
{
pos = checkPosition ( board, 0, 2 );
if ( pos )
board[0][2] = 2;
else
{
int n1, n2;
do
{
n1 = 1 + rand() % 2;
n2 = 1 + rand() % 2;

pos = checkPosition ( board, n1, n2 );
} while ( !pos );
board[n1][n2] = 2;
}
}
}
}
}

else // turn is > 5
{
//check for win situation

int i, j;
for ( i = 0; i < 3; i++ )
{
for ( j = 0; j < 3; j++ )
{
pos = checkPosition ( board, i , j );
if ( pos )
{
board[j] = 2;
testWin = won ( board, player );
if ( !testWin )
board[j] = 0;
else
break;
}
}
if ( j < 3 ) // computer won and broke from the loop
break;
}
if ( j < 3 )
{
drawgame ( board );
cout << "\nComputer WINS!";
break;
}

// block player 1 from winning
if ( j == 3 )
{
for ( i = 0; i < 3; i++ )
{
for ( j = 0; j < 3; j++ )
{
pos = checkPosition ( board, i , j );
if ( pos )
{
board[j] = 1;
testWin = won ( board, 1 );
if ( !testWin )
board[j] = 0;
else
{
board[j] = 2;
break;
}
}
}
if ( j < 3 )
break;
}
if ( j == 3 ) // computer chooses a random value
{
int n1, n2;
do
{
n1 = 1 + rand() % 2;
n2 = 1 + rand() % 2;
pos = checkPosition ( board, n1, n2 );
} while ( !pos );
board[n1][n2] = 2;
}

}
}
drawgame ( board );
}

else // player 1's turn
{
player = 1;
do
{
cout << "\nPlayer 1, Enter a position: ";
cin >> row >> col;

pos = checkPosition ( board, row, col );

if ( ! pos )
cout << "\nSorry...choose a different position! " << endl;

} while ( ! pos ); // player entered a wrong position

board [ row ][ col ] = player;
drawgame ( board );
cout<<"\n";

// test for winning position
// tests only if each player has played twice already
if ( turn > 4 )
{
bool testWin = won( board, player );
if ( testWin ) // Player Won!
{
cout << "YOU WIN!" << endl;
break;
}
}

}

turn++; // counter

} while ( turn <= 9 );

if ( turn == 10 )
cout << "\nDRAW"; // no winner
getch();
}

H

#### Howard

sabirah said:
My code does not seem to be working properly...

<snip>

What exactly is the problem you're having? Are we supposed to analyze all
your code (which really needs to be indented for us to read, by the way),
and guess where it might be going wrong? You need to tell us what the exact
problem is, what you expect to be happening, and what you are observing.
Then maybe we can concentrate on just the problem part.

-Howard

S

#### sabirah

while playing...if i choose on my first turn the bottom right corner,
the computer doesnt play. So I think the problem is with this code:

else if ( turn == 3 ) // no possibility of any wins yet...choose
strategic position
{
if ( board[0][0] == 2 )
pos = checkPosition ( board, 2, 2 );
if ( pos )
board[2][2] = 2;
else if ( board[2][2] == 2 )
{
pos = checkPosition ( board, 0, 0 );
if ( pos )
board[0][0] = 2;
else if ( board[0][2] == 2 )
{
pos = checkPosition ( board, 2, 0 );
if ( pos )
board[2][0] = 2;
else if ( board[2][0] == 2 )
{
pos = checkPosition ( board, 0, 2 );
if ( pos )
board[0][2] = 2;
else
{
int n1, n2;
do
{
n1 = 1 + rand() % 2;
n2 = 1 + rand() % 2;
pos = checkPosition ( board, n1, n2 );
} while ( !pos );
board[n1][n2] = 2;
}
}
}
}
}

and i think is primarily in my use of the rand() function.

S

#### sabirah

if i choose on my first turn the bottom right corner ( which is
board[2][2] ), the computer will not play his turn.

S

#### sabirah

in the computer's turn 3, the computer should choose a corner...and if
the corners are occupied, then choose a random position.
if i dont choose the corner the computer, will play normally. if i
choose a corner, the computer won't play.

S

#### sabirah

Thank you for making me elaborate on what my problem was...I figured
out what the problem was.

S

#### sabirah

Thank you for making me elaborate on what my problem is...I figured out
what the problem was.

H

#### Howard

sabirah said:
Thank you for making me elaborate on what my problem was...I figured
out what the problem was.

I'm glad I helped. The same thing happens to me all the time... simply
describing the problem to someone helps me figure it out.

By the way, your responses should include relevant portions of the
message(s) you're responding to, so we don't have to go back and read
previous posts to know what you're talking about. Ok?

-Howard

D

#### Default User

Howard said:
By the way, your responses should include relevant portions of the
message(s) you're responding to, so we don't have to go back and read
previous posts to know what you're talking about. Ok?

As the OP is posting from Google (no surprise) the information below
may be of value.

Brian

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