Tic Tac Toe Program

I'm creating a tic tac toe game. This is what i want to do. get the user input (a number 1-9 the corresponds to the spaces on the board) and replace it with an X or O in the array tic_tac_toe. if they want an X in postion 4 how do i write the function to replace 4 with X? This is what i have so far

Code:

#include <stdio.h> 
#include <stdlib.h> 

#define NUMBER_OF_SQUARES 9 

char tic_tac_toe[NUMBER_OF_SQUARES]={'0', '1','2', '3', '4', '5','6', '7', '8'}; 
void print_board(); 
void clear_board(); 
char get_user_character(char); 
void user_move(); 

int main() 
{ 

char choice; 
int tic_tac_toe_board; 
clear_board(); 
print_board(); 
get_user_character(choice); 
tic_tac_toe[user_move-1]=user_representation; 
return 0; 
} 


void clear_board(void) 
{ 
int i; 
for (i = 0; i < 9; i++) 
{ 
tic_tac_toe[i] = ' '; 
} 
} 

void print_board(void) 
{ 
char tic_tac_toe[NUMBER_OF_SQUARES]={'0', '1','2', '3', '4', '5','6', '7', '8'}; 

printf("  %c | %c | %c\n", tic_tac_toe[0], tic_tac_toe[1], tic_tac_toe[2]); 
printf("----+---+----\n"); 
printf("  %c | %c | %c\n", tic_tac_toe[3], tic_tac_toe[4], tic_tac_toe[5]); 
printf("----+---+----\n"); 
printf("  %c | %c | %c\n", tic_tac_toe[6], tic_tac_toe[7], tic_tac_toe[8]);        
} 

char get_user_character(char choice) 
{ 
printf("play with X or play with O\n"); 
scanf("%c", &choice); 

return (choice); 
} 


void user_move(void) 
{ 
printf("enter what box number that you\n"); 
printf("would like to place you move in> \n") 
scanf("%d",

>if they want an X in postion 4 how do i write the function to replace 4 with X?

Code:

tic_tac_toe[choice-'0'] = 'X';

You could also define choice as an int, then you wouldn't need to subtract '0' from choice, but this would introduce other problems.

Could you use a switch or if statment. i.e. if move is 4 = tic_tac_toe[choice]?

>Could you use a switch or if statment. i.e. if move is 4 = tic_tac_toe[choice]?
Do you mean like:

Code:

switch (choice)
{
	case '0':
		/* do stuff */
		break;
	case '1':
		/* do stuff */
		break;
	case '2':
		/* do stuff */
		break;
	case '3':
		/* do stuff */
		break;
	case '4':
		/* do stuff */
		break;
	case '5':
		/* do stuff */
		break;
	case '6':
		/* do stuff */
		break;
	case '7':
		/* do stuff */
		break;
	case '8':
		/* do stuff */
		break;
	default:
		/* Invalid coordinate */
		break;
}

can i do this? Shouldn't this work?

Code:

void user_move(void)
{
        char choice;
        static int i;
        printf("enter what box number that you\n");
        printf("would like to place you move in> \n");
        scanf("%d",&i);
if (i<0 || i>8)
{
                printf("invalid move\n");
}
else
        tic_tac_toe[i] = choice;

        print_board();

}

Sure, that will work fine. A problem can occur if the user accidently enters something besides a number. Better would be to use fgets() to read what the user entered, then instead of scanf(), use sscanf().

The indentation needs fixing to begin with.

I got the program to work but now the get_usermove function skips the scanf.It doesn't let me enter a positon to move it just skips it and prints invalid move....any suggestions?

Code:

#include <stdio.h> 
#include <stdlib.h> 

#define NUMBER_OF_SQUARES 9 

char tic_tac_toe[NUMBER_OF_SQUARES]={'0', '1','2', '3', '4', '5','6', '7', '8'}; 
void print_board(char*tic_tac_toe); 
void clear_board(); 
char get_user_character(); 
char user_move(char*); 

int main() 
{ 
int use_move; 
char choice; 
char tic_tac_toe_board; 
char user_representation; 

clear_board(); 
print_board( tic_tac_toe); 
get_user_character(); 
user_move(&choice); 
print_board(tic_tac_toe); 
// return EXIT_SUCCESS; 
} 

void clear_board(void) 
{ 
int i; 
for (i = 0; i < 9; i++) 
{ 
tic_tac_toe[i] = ' '; 
} 
} 
void print_board(char *tic_tac_toe) 
{ 

printf("  &#37;c | %c | %c\n", tic_tac_toe[0], tic_tac_toe[1], tic_tac_toe[2]); 
printf("----+---+----\n"); 
printf("  %c | %c | %c\n", tic_tac_toe[3], tic_tac_toe[4], tic_tac_toe[5]); 
printf("----+---+----\n"); 
printf("  %c | %c | %c\n", tic_tac_toe[6], tic_tac_toe[7], tic_tac_toe[8]);        
} 

char get_user_character() 
{ 
char choice; 
printf("Play with X or play with O\n"); 
scanf("%c", &choice); 
return (choice); 
} 

char user_move(char *choice) 
{ 
char i; 
printf("Enter what box number that you\n"); 
printf("would like to place you move in>\n"); 
scanf("%c", &i); 

if (i <0 || i>8) 
printf("invalid move\n"); 
else 
tic_tac_toe[i] = *choice; 


} 
output:

    |   |  
----+---+----
    |   |  
----+---+----
    |   |  
Play with X or play with O
X
Enter what box number that you
would like to place you move in>
invalid move
    |   |  
----+---+----
    |   |  
----+---+----
    |   |

i should be an int, not a char. (There is no way to get a character with value 0 from the keyboard that I know of, and 1-8 are pretty tricky too.)

ok. tabstop when i have it at int this is the output:

Code:

    |   |  
----+---+----
    |   |  
----+---+----
    |   |  
Play with X or play with O
X
Enter what box number that you
would like to place you move in>
4
    |   |  
----+---+----
    | ¿ |  
----+---+----
    |   |

Am i not passing choice into the array tic_tac_toe correctly?

You need to set tic_tac_toe[i] to 'X', not 'random uninitialized variable'.

Edit: IOW, the choice in main() and the choice in get_user_character() aren't the same. You return it from get_user_character, but main doesn't do anything with it.

ok in main() i changed char choice to char *choice and user_move(&choice) to user_move(choice).... output now is:

Code:

    |   |  
----+---+----
    |   |  
----+---+----
    |   |  
Play with X or play with O
X
Enter what box number that you
would like to place you move in>
4
    |   |  
----+---+----
    | U |  
----+---+----
    |   |

That has nothing to do with the problem. get_user_choice is a function that returns a character. You must put that character somewhere by assigning the result of the function to a variable.

thanks tabstop I finally see the light Okay now is this is my new main function. I added function get_a_winner to check a winner and it works. What I want to do is end program when a winner is found using the check winner function. How would I do that in my main function if I have the loop set for 9 iterations?

Code:

int main()
{
        int j;
        clear_board(tic_tac_toe);
        print_board( tic_tac_toe);

        char choice =get_user_character();
for (j=0; j<9; j++)
{
        int i =user_move(tic_tac_toe);
        tic_tac_toe[i-1]= choice;
        print_board(tic_tac_toe);
        get_a_winner(tic_tac_toe);
}
        return EXIT_SUCCESS;
}



char get_a_winner(char*tic_tac_toe)
{
        
if((tic_tac_toe[0] == 'X') && (tic_tac_toe[1] =='X') && (tic_tac_toe[2]=='X')||
   (tic_tac_toe[3] == 'X') && (tic_tac_toe[4] =='X') && (tic_tac_toe[5]=='X')||
   (tic_tac_toe[6] == 'X') && (tic_tac_toe[7] =='X') && (tic_tac_toe[8]=='X')||
   (tic_tac_toe[0] == 'X') && (tic_tac_toe[3] =='X') && (tic_tac_toe[6]=='X')||
   (tic_tac_toe[1] == 'X') && (tic_tac_toe[4] =='X') && (tic_tac_toe[7]=='X')||
   (tic_tac_toe[2] == 'X') && (tic_tac_toe[5] =='X') && (tic_tac_toe[8]=='X')||
   (tic_tac_toe[0] == 'X') && (tic_tac_toe[4] =='X') && (tic_tac_toe[8]=='X')||
   (tic_tac_toe[2] == 'X') && (tic_tac_toe[4] =='X') && (tic_tac_toe[6]=='X'))

        printf("player X is the winner\n");

}

Originally Posted by marquis1431

thanks tabstop I finally see the light Okay now is this is my new main function. I added function get_a_winner to check a winner and it works. What I want to do is end program when a winner is found using the check winner function. How would I do that in my main function if I have the loop set for 9 iterations?

Don't set your loop for 9 iterations, but instead use the result of your winner check. IOW: You want to do something while there's no winner.

Note that you're get a winner function claims to return char, but does not do so -- you'll need to decide what to return for X winning, what to return for O winning, what to return for a cat game, and what to return for a game still in progress.