How to reset array in my tic tac toe game - arrays

Question

I'm new to C and I'm trying to make a tic-tac-toe game for my college project and I'm struggling on how to reset my array in my game.
Every time I play again it does not reset the array. Can anyone help me with this?
Here is the code:
#include <stdio.h>
#include <conio.h>
#include <stdlib.h>
char space[3][3] = {
{'1','2','3'},
{'4','5','6'},
{'7','8','9'}
};
void board();
int checkWin();
int game();
void reset();
int main(){
int choice = -1;
do{
printf("\n\n\n\n\n\n\n\t\t\t ================\n");
printf("\t\t\t Tic Tac Toe\n");
printf("\t\t\t ================\n");
printf("\t\t -----------Menu-----------\n\n");
printf("\t\t 1. Play\n");
printf("\t\t 2. Exit\n");
scanf("%d", &choice);
switch(choice){
case 1: game();
break;
case 2: printf("Goodbye!!");
exit(0);
break;
default: printf(".......Wrong Key !.......Try Again!......");
break;
}
}while(choice != 0);
}
int game(){
int player = 1, i, choice;
char mark;
do
{
system("cls");
board();
player = (player % 2) ? 1 : 2;
printf("Player %d, enter a number: ", player);
scanf("%d", &choice);
mark = (player == 1) ? 'X' : 'O';
if (choice == 1)
space[0][0] = mark;
else if (choice == 2)
space[0][1] = mark;
else if (choice == 3)
space[0][2] = mark;
else if (choice == 4)
space[1][0] = mark;
else if (choice == 5)
space[1][1] = mark;
else if (choice == 6)
space[1][2] = mark;
else if (choice == 7)
space[2][0] = mark;
else if (choice == 8)
space[2][1] = mark;
else if (choice == 9)
space[2][2] = mark;
else
{
printf("Invalid move ");
player--;
getch();
}
i = checkWin();
player++;
}while (i == - 1);
board();
reset();
if (i == 1)
printf("==>\aPlayer %d win \n\n", --player);
else
printf("==>\aGame draw\n\n");
getch();
return 0;
}
int checkWin(){
if (space[0][0] == space[0][1] && space[0][1] == space[0][2])
return 1;
else if (space[1][0] == space[1][1] && space[1][1] == space[1][2])
return 1;
else if (space[2][0] == space[2][1] && space[2][1] == space[2][2])
return 1;
else if (space[0][0] == space[1][0] && space[1][0] == space[2][0])
return 1;
else if (space[0][1] == space[1][1] && space[1][1] == space[2][1])
return 1;
else if (space[0][2] == space[1][2] && space[1][2] == space[2][2])
return 1;
else if (space[0][0] == space[1][1] && space[1][1] == space[2][2])
return 1;
else if (space[0][2] == space[1][1] && space[1][1] == space[2][0])
return 1;
else if (space[0][0] != space[0][0] && space[0][1] != space[0][1] && space[0][2] != space[0][2] &&
space[1][0] != space[1][0] && space[1][1] != space[1][1] && space[1][2] != space[1][2] && space[2][0]
!= space[2][0] && space[2][1] != space[2][1] && space[2][2] != space[2][1])
return 0;
else
return - 1;
}
void reset(){
for (int i = 0; i < 3; i++)
{
for (int j = 0; j < 3; j++)
{
space[i][j] = 0;
}
}
}
void board(){
system("cls");
printf("\n\n\tTic Tac Toe\n\n");
printf("Player 1 (X) - Player 2 (O)\n\n\n");
printf(" | | \n");
printf(" %c | %c | %c \n", space[0][0], space[0][1], space[0][2]);
printf("_____|_____|_____\n");
printf(" | | \n");
printf(" %c | %c | %c \n", space[1][0], space[1][1], space[1][2]);
printf("_____|_____|_____\n");
printf(" | | \n");
printf(" %c | %c | %c \n", space[2][0], space[2][1], space[2][2]);
printf(" | | \n\n");
}
I tried using for loop but it does not work; how can I solve this?
void reset(){
for (int i = 0; i < 3; i++)
{
for (int j = 0; j < 3; j++)
{
space[i][j] = 0;
}
}
}

Answer 1

Your reset function is filling the entire 3x3 board matrix with zeros; these represent the nul character, not the character representing the '0' digit. Those nul characters aren't printed (and cannot be), so the board looks 'wrong' after a reset.
However, simply changing the space[i][j] = 0; line to space[i][j] = '0'; won't work! Although you will then initially see a board full of 0 digits, the way your checkWin() function works will then ensure that "Player 1" will have won the new game immediately after their first move, because there will already be rows/columns/diagonals of three identical characters.
So, to get the original ('1' thru '9') display, write your reset() function as below. (Note that the C Standard requires that the characters representing the numerical digits be in order and contiguous, so adding a value of 1 thru 9 to the '0' character will yield the appropriate digit character.)
void reset()
{
int number = 1;
for (int i = 0; i < 3; i++)
{
for (int j = 0; j < 3; j++)
{
space[i][j] = number++ + '0';
}
}
}
Alternatively, you can just declare and initialize a new 'board array' with the data in it, then just use memcpy to rest the space array with the contents of that:
#include <string.h> // For "memcpy"
void reset()
{
char empty[3][3] = { {'1','2','3'}, {'4','5','6'}, {'7','8','9'} };
memcpy(space, empty, sizeof(space));
}
Note, also that all the tests in the following statement are wrong:
else if (space[0][0] != space[0][0] && space[0][1] != space[0][1] && space[0][2] != space[0][2] &&
space[1][0] != space[1][0] && space[1][1] != space[1][1] && space[1][2] != space[1][2] && space[2][0]
!= space[2][0] && space[2][1] != space[2][1] && space[2][2] != space[2][1])
Each one of these is testing if an element is not equal to itself. This can never be true, so that else if block (the return 0; line) is never executed. But you don't actually need it, so you can just delete that block.