tictaktoe Array bound overflow - c++

Question

I am in need of help for this code that i am working on for a assignment. I am have the issue where if i have any X's on the board that is either in the left 2 columns it will display a X in the row above. I used my debugger and it seems that it is trying to access something outside the array bounds, but it shouldnt be. any advice on how to do this?
#include <iostream>
using namespace std;
void printTTT(char a[3][3]);
void insertX(/*PASS BY REFERENCE*/);
void insertO(char (&arr)[3][3]);
void checkForWin(/*PASS BY REFERENCE*/); // IGNORE THIS FOR NOW
int main() {
char TTTarray[3][3] = { { 'X','-','-' },
{ '-','-','-' },
{ 'X','-','-' } };
//char TTTarray[3][3] = { {'-','X','-'},
// {'-','X','-'},
// {'-','-','O'}};
//char TTTarray[3][3] = { {'-','-','-'},
// {'-','X','-'},
// {'-','O','-'}};
//char TTTarray[3][3] = { {'X','-','X'},
// {'-','-','-'},
// {'O','-','-'}};
//char TTTarray[3][3] = { {'X','-','X'},
// {'O','X','-'},
// {'O','-','O'}};
//insertX(/*CALL*/);
//OR
insertO(TTTarray);
printTTT(TTTarray);
/*****************
I have included the declaratoin of the array, initialized to - for each spot.
The '-' represents an empty position. You should fill it with either a
capital 'O' or a capital 'X'. I have also included a number of initialized arrays
to test; just comment out the ones you don't want for that moment
*****************/
return 0;
}
void printTTT(char a[3][3])
{
for (int i = 0; i < 3; i++)
{
for (int j = 0; j < 3; j++)
{
cout << a[i][j];
}
cout << endl;
}
}
void insertX(/*PASS BY REFERENCE*/) {
}
void insertO(char (&arr)[3][3])
{
int x1x;
int x1y;
//int x2x;
//int x2y;
for (int i = 0; i < 3; i++)
{
int go = 0;
for (int j = 0; j < 3; j++)
{
if (arr[i][j] == '-')
{
x1x = i;
x1y = j;
// looking for 2 x's for the block lol
if (x1x == 0 && go == 0)
{
if (arr[x1x][x1y + 1] == 'X' && arr[x1x][x1y + 2] == 'X')
{
arr[i][j] = 'O';
go = 1;
}
if (arr[x1x][x1y - 1] == 'X' && arr[x1x][x1x + 1] == 'X')
{
arr[i][j] = 'O';
go = 1;
}
if (arr[x1x][x1y - 1] == 'X' && arr[x1x][x1x - 2] == 'X')
{
arr[i][j] = 'O';
go = 1;
}
}
if (x1x == 1 && go == 0)
{
if (arr[x1x][x1y + 1] == 'X' && arr[x1x][x1y + 2] == 'X')
{
arr[i][j] = 'O';
go = 1;
}
if (arr[x1x][x1y - 1] == 'X' && arr[x1x][x1x + 1] == 'X')
{
arr[i][j] = 'O';
go = 1;
}
if (arr[x1x][x1y - 1] == 'X' && arr[x1x][x1x - 2] == 'X')
{
arr[i][j] = 'O';
go = 1;
}
}
if (x1x == 2 && go == 0)
{
if (arr[x1x][x1y + 1] == 'X' && arr[x1x][x1y + 2] == 'X')
{
arr[i][j] = 'O';
go = 1;
}
if (arr[x1x][x1y - 1] == 'X' && arr[x1x][x1x + 1] == 'X')
{
arr[i][j] = 'O';
go = 1;
}
if (arr[x1x][x1y - 1] == 'X' && arr[x1x][x1x - 2] == 'X')
{
arr[i][j] = 'O';
go = 1;
}
}
if (x1y == 0 && go == 0)
{
if (arr[x1x + 1][x1y] == 'X' && arr[x1x + 2][x1y] == 'X')
{
arr[i][j] = 'O';
go = 1;
}
if (arr[x1x - 1][x1y] == 'X' && arr[x1x + 1][x1x] == 'X')
{
arr[i][j] = 'O';
go = 1;
}
if (arr[x1x - 1][x1y] == 'X' && arr[x1x - 2][x1x] == 'X')
{
arr[i][j] = 'O';
go = 1;
}
}
if (x1y == 1 && go == 0)
{
if (arr[x1x + 1][x1y] == 'X' && arr[x1x + 2][x1y] == 'X')
{
arr[i][j] = 'O';
go = 1;
}
if (arr[x1x - 1][x1y] == 'X' && arr[x1x + 1][x1x] == 'X')
{
arr[i][j] = 'O';
go = 1;
}
if (arr[x1x - 1][x1y] == 'X' && arr[x1x - 2][x1x] == 'X')
{
arr[i][j] = 'O';
go = 1;
}
}
if (x1y == 2 && go == 0)
181,1-8 83%
{
if (arr[x1x + 1][x1y] == 'X' && arr[x1x + 2][x1y] == 'X')
{
arr[i][j] = 'O';
go = 1;
}
if (arr[x1x - 1][x1y] == 'X' && arr[x1x + 1][x1x] == 'X')
{
arr[i][j] = 'O';
go = 1;
}
if (arr[x1x - 1][x1y] == 'X' && arr[x1x - 2][x1x] == 'X')
{
arr[i][j] = 'O';
go = 1;
}
}
}
}
}
}

Answer 1

Take a look at these lines from your insertD function:
if (x1x == 0 && go == 0)
{
if (arr[x1x][x1y + 1] == 'X' && arr[x1x][x1y + 2] == 'X')
In this case you have checked that x1x is zero, but you haven't checked x1y. So in this case you will go out of bounds if x1y is non-zero.
A couple of lines below you have
if (arr[x1x][x1y - 1] == 'X' && arr[x1x][x1x + 1] == 'X')
This will go out of bounds too, when x1y is zero.
You need to add more checks, or rethink the logic.