This is my homework

It is a tic-tac-toe game, this game is played by two players user1 and 2 and I have to use the 2-D arrys, I tried to solve it but there is some mistakes, I think there is a mistake in the loop or some thig else.

you can check the attachment
NOTE: the explination of the functions is writen as comments in the program



#include <stdio.h>
void init_board(void);
void draw_board(void);

void play_game(void);
int play_again(void);

void user1_move(void);
void user2_move(void);
int find_win(char);
int middle_open(void);
int symbol_won(char);
int square_valid(int);

char board[3][3];
char user1, user2;

/* Initialize the board, ask who goes first, play a game, ask if user wants to play again. */
int main(void)
{
while(1)
{

init_board();
user1 = 'X';
user2 = 'O';


play_game();
if (!play_again())
break;
}

return (0);
}

/* Make sure board starts off empty. */
void init_board(void)
{
int row, col;

for (row = 0; row < 3; row++)
for (col = 0; col < 3; col++)
board[row][col] = ' ';


}

/* Display the board to standard output. */
void draw_board(void)
{
int row, col;

printf("\n");
for (row = 0; row < 3; row++)
{
printf(" * * \n");
printf(" %c * %c * %c \n", board[row][0], board[row][1], board[row][2]);
printf(" * * \n");
if (row != 2)
printf("***********\n");
}
printf("\n");

return;
}


void play_game(void)
{
int turn;

for (turn = 1; turn <= 9; turn++)
{
/* Check if turn is even or odd to determine which player should move. */
if (turn % 2 == 1)
{
if (user1 == 'X')
user1_move();
else
user2_move();
}
else
{
if (user2 == 'O')
user2_move();
else
user1_move();
}

draw_board();

if (symbol_won(user2)) {
printf("\n PLAYER 2 WIN!!!\n\n");
return;
}
else if (symbol_won(user1)) {
printf("\n PLAYER 1 WIN!\n\n");
return;
}
}

printf("\nThe game is a draw.\n\n");
return;
}

/* Ask if user wants to play again. Returns 1 if yes, 0 if no. */
int play_again(void)
{
char response;

printf("Do you want to play again? (y/n) ");
do
{
response = getchar();
} while ((response != 'y') && (response != 'Y') &&
(response != 'n') && (response != 'N'));

if ((response == 'y') || (response == 'Y'))
return 1;
else
return 0;
}
void user1_move(void)
{
int square;
int row, col;

/* Use first strategy rule that returns valid square */
square = find_win(user1);
if (!square)
square = find_win(user2);
if (!square)
square = middle_open();



row = (square - 1) / 3;
col = (square - 1) % 3;

board[row][col] = user1;

return;
}

/* Choose a move for the computer. */
void user2_move(void)
{
int square;
int row, col;

/* Use first strategy rule that returns valid square */
square = find_win(user2);
if (!square)
square = find_win(user1);
if (!square)
square = middle_open();



row = (square - 1) / 3;
col = (square - 1) % 3;

board[row][col] = user2;

return;
}

/*
* Find a win, if any, for the given symbol.
* If a winning square exists, return the square;
* Otherwise, return 0;
*/
int find_win(char symbol)
{
int square, row, col;
int result = 0;

/*
* Loop through the 9 squares.
* For each, if it is empty, fill it in with the given symbol and check
* if this has resulted in a win. If so, keep track of this square in result.
* Either way, reset the square to empty afterwards. After the loop, if one or
* more wins have been found, the last will be recorded in result.
* Otherwise, result will still be 0.
*/
for (square = 1; square <= 9; square++)
{
row = (square - 1) / 3;
col = (square - 1) % 3;

if (board[row][col] == ' ')
{
board[row][col] = symbol;
if (symbol_won(symbol))
result = square;
board[row][col] = ' ';
}
}

return result;
}

/* If middle square is empty, return 5; Otherwise return 0. */
int middle_open(void)
{
if (board[1][1] == ' ')
return 5;
else
return 0;
}



/* Check if the given symbol has already one the game. */
int symbol_won(char symbol)
{
int row, col;

for (row = 0; row < 3; row++)
{
if ((board[row][0] == symbol) && (board[row][1] == symbol) && (board[row][2] == symbol))
return 1;
}

for (col = 0; col < 3; col++)
{
if ((board[0][col] == symbol) && (board[1][col] == symbol) && (board[2][col] == symbol))
return 1;
}

if ((board[0][0] == symbol) && (board[1][1] == symbol) && (board[2][2] == symbol))
return 1;

if ((board[0][2] == symbol) && (board[1][1] == symbol) && (board[2][0] == symbol))
return 1;

return 0;
}




/* Check if the given square is valid and empty. */
int square_valid(int square)
{
int row, col;

row = (square - 1) / 3;
col = (square - 1) % 3;

if ((square >= 1) && (square <= 9))
{
if (board[row][col] == ' ')
return 1;
}

return 0;


}

This post has been edited by bader: 21 May, 2008 - 06:15 AM