Cant make the maze work correctly with arrays

[Codedexter]

I have to make a maze with arrays, but i cant seem to move down or up or at all. Any help would be greatly appreciated.
Here is what I have so far


#include <iostream>
#include <string>
#include <iomanip>
#include <fstream>
#include <cmath>

using namespace std;

void up(int &, int &);
void down(int &, int &);
void left(int &, int &);
void right(int &, int &);

int main()
{

char maze[30][20];
ifstream inputFile;
inputFile.open("E:/maze.txt");


inputFile.close();

int playerX = 1;
int playerY = 0;
bool game = false;


system("cls");
for (int i = 0; i<30; i++)
{
for (int j = 0; j<20; j++)
{
cout << maze[i][j];
}

cout << endl;
}


do
{

system("cls");
for (int i = 0; i<30; i++)
{
for (int j = 0; j<20; j++)
{
cout << maze[i][j];
}

cout << endl;
}


cout << "You are currently at (" << playerX << "," << playerY << ")" << endl;
cout << "Where would you like to move next? (Up = U, Down = D, Left = L, Right = R)" << endl;
char UserMove;
cin >> UserMove;


UserMove = toupper(UserMove);
if (UserMove == 'U')
{
up(playerX, playerY);
}
else if (UserMove == 'D')
{
down(playerX, playerY);
}
else if (UserMove == 'L')
{
left(playerX, playerY);
}
else if (UserMove == 'R')
{
right(playerX, playerY);
}
else
{
cout << "Invalid, please choose another." << endl;
system("pause");
}


if (playerX == 29 && playerY == 20)
{
game = true;
}

} while (game == false);

system("cls");
cout << "Winner!!" << endl;

system("pause");
return 0;
}

void up(int &playerX, int &playerY)
{

char maze[30][20];
int prevplayerX = playerX;
int prevplayerY = playerY;

if (maze[playerX][playerY - 1] == '#')
{
playerY--;

maze[prevplayerX][prevplayerY] = '#';
}



}

void down(int &playerX, int &playerY)
{


char maze[30][20];
int prevplayerX = playerX;
int prevplayerY = playerY;

if (maze[playerX][playerY - 1] == '#')
{
playerY++;

maze[prevplayerX][prevplayerY] = '#';
}



}

void left(int &playerX, int &playerY)
{


char maze[30][20];
int prevplayerX = playerX;
int prevplayerY = playerY;

if (maze[playerX][playerY - 1] == '#')
{
playerY--;

maze[prevplayerX][prevplayerY] = '#';
}



}

void right(int &playerX, int &playerY)
{

}

[VictorN]

I have to make a maze with arrays, but i cant seem to move down or up or at all. Any help would be greatly appreciated.
Here is what I have so far
...

First you have to use Code tags to make your code snippets readable. Compare what you posted with how it should look like:

#include <iostream>
#include <string>
#include <iomanip>
#include <fstream>
#include <cmath>

using namespace std;

void up(int &, int &);
void down(int &, int &);
void left(int &, int &);
void right(int &, int &);

int main()
{
	char maze[30][20];
	ifstream inputFile;
	inputFile.open("E:/maze.txt");

	inputFile.close();

	int playerX = 1;
	int playerY = 0;
	bool game = false;

	system("cls");
	for (int i = 0; i<30; i++)
	{
		for (int j = 0; j<20; j++)
		{
			cout << maze[i][j];
		}
		cout << endl;
	}
	do
	{
		system("cls");
		for (int i = 0; i<30; i++)
		{
			for (int j = 0; j<20; j++)
			{
				cout << maze[i][j];
			}

			cout << endl;
		}

		cout << "You are currently at (" << playerX << "," << playerY << ")" << endl;
		cout << "Where would you like to move next? (Up = U, Down = D, Left = L, Right = R)" << endl;
		char UserMove;
		cin >> UserMove;

		UserMove = toupper(UserMove);
		if (UserMove == 'U')
		{
			up(playerX, playerY);
		}
		else if (UserMove == 'D')
		{
			down(playerX, playerY);
		}
		else if (UserMove == 'L')
		{
			left(playerX, playerY);
		}
		else if (UserMove == 'R')
		{
			right(playerX, playerY);
		}
		else
		{
			cout << "Invalid, please choose another." << endl;
			system("pause");
		}

		if (playerX == 29 && playerY == 20)
		{
			game = true;
		}

	} while (game == false);

	system("cls");
	cout << "Winner!!" << endl;

	system("pause");
	return 0;
}

void up(int &playerX, int &playerY)
{
	char maze[30][20];
	int prevplayerX = playerX;
	int prevplayerY = playerY;

	if (maze[playerX][playerY - 1] == '#')
	{
		playerY--;

		maze[prevplayerX][prevplayerY] = '#';
	}
}

void down(int &playerX, int &playerY)
{
	char maze[30][20];
	int prevplayerX = playerX;
	int prevplayerY = playerY;

	if (maze[playerX][playerY - 1] == '#')
	{
		playerY++;

		maze[prevplayerX][prevplayerY] = '#';
	}
}

void left(int &playerX, int &playerY)
{
	char maze[30][20];
	int prevplayerX = playerX;
	int prevplayerY = playerY;

	if (maze[playerX][playerY - 1] == '#')
	{
		playerY--;

		maze[prevplayerX][prevplayerY] = '#';
	}
}

void right(int &playerX, int &playerY)
{
}

Second, you use the local arrays

 	char maze[30][20];

in your functions left, down, up. All these arrays are NOT initialized, therefore they contain some garbage. So why do you compare this garbage with something meaningful?

[ahoodin]

Hmm try to make a maze class and make the arrays member variables belonging to the class. That may help.

[2kaud]

You open a file, do nothing with it and then close it again? Does this file contain some info about the maze? If so then will need to read the data from the file and use it to initialize the maze array.

Which brings me on to... You display the contents of the array maze without first initializing it - so the contents are unknown and are whatever happens to be at the memory address of maze each time the program is run. You also initially display it twice - once before the do loop and then again from within the do loop????

The array maze defined in main() and also again in up(), down() and left() are different variables (although they have the same name). They do not refer to the same memory contents. See the link to scope in http://msdn.microsoft.com/en-us/library/k1f45exx.aspx

There are various ways to have the up(), down() functions etc refer to the same array maze as used in main() but a good method would be to use a class as suggested by ahoodin in his post #3. The array maze would then be a private member of the class with up(), down() etc being public class functions.

[Codedexter]

Sorry im new at this :/ thanks for the help

[Codedexter]

thanks so much 2kaud