Program written in C, loops indefinately or crashes after a while - c

Question

this is both my first time asking a question and also one of my first times writting such a big programm. As you might guess im new at programming.
Alright the source code:
#include <stdio.h>
typedef struct{
int **a;
int size;
}_board;
typedef _board* board;
typedef struct{
int row,col;
}position;
int main () {
int i, j, turn=1, victory = 0, num=0;
_board b;
char P1symbol, P2symbol, mark, boardarray[b.size][b.size];
position p;
printf("WELCOME TO THE GAME OF TIC TAC TOE!\n");
do {
printf("\nwill player one, use X or O as his symbols? select by pressing x or o\n");
scanf(" %c", &P1symbol);
if (P1symbol == 'x' || P1symbol == 'o') {
num = 1;
}
} while ( num == 0);
if (P1symbol == 'x') {
P2symbol = "o";
}
else {
P2symbol = "x";
}
do {
printf("\n now choose the size of the game board, type a numeral and press enter");
scanf("%d", &b.size);
}while (b.size <= 0);
for (i=0; i=b.size; i++){
for (j=0; j=b.size; j++){
boardarray[i][j] = "-";
}
}
do {
do {
boardsketch(boardarray, b.size);
if (turn%2 == 1) {
printf("player 1, please choose a box to input you mark on");
mark = P1symbol;
}else{
printf("player 2, please choose a box to input you mark on");
mark = P2symbol;
}
printf("type the coordinates i,j, which correspond to the row and collumn number");
printf("make sure the numbers are valid, not taken, and between 0 and %d", b.size);
scanf("%d %d", &p.row, &p.col);
}while (p.row > b.size && p.row < 0 && p.col > b.size && p.col <0 && boardarray[p.row][p.row] != "-");
turn++;
boardarray[p.row][p.col] = mark;
} while (wincheck(boardarray, p.row, p.col, b.size) != 1);
return 0;
}
int wincheck(int row, int col, int size, char boardarray[size][size])
{
if (boardarray[row][col] = boardarray[row -1][col -1] = boardarray[row +1][col +1]) {
return 1;
}
if (boardarray[row][col] = boardarray[row -1][col] = boardarray[row +1][col]) {
return 1;
}
if (boardarray[row][col] = boardarray[row][col -1] = boardarray[row][col +1]){
return 1;
}
if (boardarray[row][col] = boardarray[row -1][col +1] = boardarray[row +1][col -1]){
return 1;
}
}
void boardsketch(int size, char boardarray[size][size]) {
int i, j;
for (i=0; i=size; i++) {
for (j=0; j=size; j++) {
if (boardarray[i][j] == '-') {
printf("| ");
} else {
printf("%c |", &boardarray[i][j]);
}
}
}
}
Now the program's purpose is to simulate a game of tic tac toe (with the addition of the user, deciding the size of the game board). My problem is that, altough compilation IS achieved the program does 2 wierd behaviors when reaching a specific line, that line being:
do {
printf("\n now choose the size of the game board, type a numeral and press enter");
scanf("%d", &b.size);
}while (b.size <= 0);
If i input a value that doesnt obey to b.size <= 0, the printf above, repeats indefinately, if i DO put a correct value, the programm doesnt resume. What am i doing wrong? again im new at programming sooooo... go easy on me :D

Answer 1

There are compiler errors in your code. I don't know how you got it to compile and build it the first place.
Compiler errors:
You have:
P2symbol = "o";
Type of "o" is char const*. The type of P2symbol is char. What you need is
P2symbol = `o`;
Few lines after that, you have:
P2symbol = "x";
That needs to be changed to:
P2symbol = `x`;
Few lines after that, you have:
boardarray[i][j] = "-";
It suffers from the same compiler error. You need to change it to:
boardarray[i][j] = `-`;
Your declaration and definition of boardsketch does not match with the way you are calling it. Your call is:
boardsketch(boardarray, b.size);
You have defined it as:
void boardsketch(int size, char boardarray[size][size]) {
....
}
You need to change either the call or the function definition so that they match. Also, you should declare the function before it is used. Add
void boardsketch(int size, char boardarray[size][size]);
before the start of main.
The definition and call of wincheck suffers from the same error. It also should have a declaration before it's usage.
A few lines after that call to boardarray, you have the line:
}while (p.row > b.size && p.row < 0 && p.col > b.size && p.col <0 && boardarray[p.row][p.row] != "-");
The last part of that statement suffers from the char and char const* mismatch. You need to change it to:
}while (p.row > b.size && p.row < 0 && p.col > b.size && p.col <0 && boardarray[p.row][p.row] != '-');
Run Time Errors:
You have:
_board b;
char P1symbol, P2symbol, mark, boardarray[b.size][b.size];
The problem with that is b.size is not initialized. It could be anything. Using it to declare broadarray is problem. Imagine the chaos that will ensue if the b.size were to be initialized to a negative number. For sane and predictable behavior, you should initialize b properly before using its data.
A few lines below, you are asking for size to be input by the user.
do {
printf("\n now choose the size of the game board, type a numeral and press enter");
scanf("%d", &b.size);
}while (b.size <= 0);
There is a logic error here. You are asking for the size of the board after you have already created boardarray. What you could do is gather the initial input and use them to call another function where the core of the game play happens.
/* Function that contains the core part of playing the game */
void playgame(char P1symbol, char P2symbol, int size)
{
int i, j, turn=1, victory = 0;
char mark, boardarray[size][size];
position p;
for (i=0; i=size; i++){
for (j=0; j=size; j++){
boardarray[i][j] = '-';
}
}
do {
do {
boardsketch(size, boardarray);
if (turn%2 == 1) {
printf("player 1, please choose a box to input you mark on");
mark = P1symbol;
}else{
printf("player 2, please choose a box to input you mark on");
mark = P2symbol;
}
printf("type the coordinates i,j, which correspond to the row and collumn number");
printf("make sure the numbers are valid, not taken, and between 0 and %d", size);
scanf("%d %d", &p.row, &p.col);
}while (p.row > size && p.row < 0 && p.col > size && p.col <0 && boardarray[p.row][p.row] != '-');
turn++;
boardarray[p.row][p.col] = mark;
} while (wincheck(p.row, p.col, size, boardarray) != 1);
}
Now, main can be simplified to:
int main () {
char P1symbol;
char P2symbol;
int size;
int num = 0;
printf("WELCOME TO THE GAME OF TIC TAC TOE!\n");
do {
printf("\nwill player one, use X or O as his symbols? select by pressing x or o\n");
scanf(" %c", &P1symbol);
if (P1symbol == 'x' || P1symbol == 'o') {
num = 1;
}
} while ( num == 0);
if (P1symbol == 'x') {
P2symbol = 'o';
}
else {
P2symbol = 'x';
}
do {
printf("\n now choose the size of the game board, type a numeral and press enter");
scanf("%d", &size);
}while (size <= 0);
playgame(P1symbol, P2symbol, size);
return 0;
}

Answer 2

Ah, the problem is your for loop after the do while. You are assigning your counters instead of evaluating the limits. Asigning them will result to true every time. Try this instead:
for (i=0; i<b.size; i++){
for (j=0; j<b.size; j++){
boardarray[i][j] = "-";
}
}
Also, do not create an array with undefine value b.size...