Thread: Arrays

I have a an array tic_tac_toe[9] with numbers 0-8 in the array. I want to get an user input and replace it with one of the humbers within the array and then display the array via the print_board function which prints the array. How would i do that. This is what i have but the arry doesnt reflect the new user inputed value.

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] = 9;
        print_board();
}
        
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]);
}

Code:

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

I don't see any way to change those numbers, since you go straight into printf. You have to communicate between functions. Pass that tic_tac_toe that you fiddled with in user_move off to print_board.

To pass the tic_tac_toe[] i would need to get rid of the decliration in the function print_board and pass it to print_baord after it's changed in the function use_move?

Example:

Code:

int handle_keys(char tic_tac_toe[NUMBER_OF_SQUARES]);
int print_board(char tic_tac_toe[NUMBER_OF_SQUARES]);

int main(void)
{
   char tic_tac_toe[NUMBER_OF_SQUARES];

   while(handle_keys(tic_tac_toe))
   {
       print_board(tic_tac_toe);
   }
}

You can go ahead and define handle_keys() and print_board().

Ok here is the program. I'm trying to put the user's move, either X or O in the array postion that they chose and display the board again with the X or O in that positon. It isn't working though.

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); 
void user_move(); 

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(choice); 
user_move(); 
print_board(tic_tac_toe); 
return 0; 
} 


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); 
} 

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; 
}

my output is:
| |
----+---+----
| |
----+---+----
| |
play with X or play with O
X
enter what box number that you
would like to place you move in>
3
| |
----+---+----
| |
----+---+----
| |
Kinda wierd. can't figure out how to pass the X or O into the array and display it correctly.

i changed my user_move to char user_move(char); and the function to char user_move(char choice)
now my output is:

| |
----+---+----
| |
----+---+----
| |
play with X or play with O
X
enter what box number that you
would like to place you move in>
3
| |
----+---+----
 | |
----+---+----
| |


It puts the character in the space where i want it but it puts an arbirtrary character not X.

I changed my scanf()'s to %c when i did that it doesnt allow me to input an positon ont he board. it bypasses the below code and prints invalid move and the new board....what could be wrong with that code?

Code:

        scanf("%c", &i);