Thread: Multi-Dimensional Array Question

With arrays.. you should always try to take advantage of using loops.. many ways you could tackle this problem.. here is one perspective. Take a look at load_grid( ) and see how I used loops to handle loading the bars into the array. I could have used nested for loops... but I decided just to hard code one dimenstion and then use a loop counter to increment through the second dimension (thus loading the grid into the 2D array 'line at a time')

Code:

#include<iostream>
#include<cstdlib>
#include<iomanip>
#include<cctype>
using namespace std;


class TicTac
{

public:

	TicTac();
	void load_grid();
	void display_grid();
	void prompt_player();
	void update_grid();	
	void set_turn();
	bool check_winner();
	void reset();

private:

	char grid[5][6];
	char square;
	int  turn;	
	int  turn_counter;
	bool tie;
};


char again();

int main()
{
	TicTac Toe;

	Toe.load_grid();

	do{
		Toe.reset();		

		Toe.display_grid();

		do{	
			Toe.prompt_player();			
	
			Toe.update_grid();	
			
			Toe.set_turn();

			Toe.display_grid();			

		}while(!Toe.check_winner());	 

	}while(again()!='N');

	return 0;
}



//FUNCTION DEFINITIONS

TicTac::TicTac()
{
	for(int row=0; row<5; row++)
		for(int column=0; column<5; column++)

			grid[row][column]='0';

	turn	= 1;
	tie     = 0;
}


void TicTac::load_grid()
{

	for(int row=0;row<5;row+=2)
	
		grid[row][1]=grid[row][3]=(char)179;

	for(row=1;row<4;row+=2)

		grid[row][0]=grid[row][1]=grid[row][2]=grid[row][3]=grid[row][4]=(char)196;

	for(row=0;row<6;row++)

		grid[row][5]='\0';
}

	
void TicTac::display_grid()
{
	int spacer;

	if(turn==1)
		spacer = 20;	
	else 
		spacer = 39;


	system("cls");

	if(tie)

		cout << "\a\n\n\t   *** Tie!!  No Winners!!  ***\n";

	else if(check_winner())

		cout << "\a\n\n\t   *** Player " << turn << " weeens! ***\n";

	else 
	
		cout << "\n\n\tPlayer 1 = X       Player 2 = O\n" << setw(spacer) << "------------";	
		

	cout << endl << endl << endl << endl;

	for(int row=0;row<5;row++)
	
		cout << setw(25) << grid[row] << endl;
}


void TicTac::prompt_player()
{
	cout << endl << endl << endl; 

	cout << "\tPlayer " << turn << ", Enter a Square: ";	
	cin  >> square;
	cin.ignore(1000,'\n');

	square=toupper(square);	
	turn_counter++;
}


void TicTac::update_grid()
{
	bool found = false;

	for(int row=0;!found && row<5; row+=2)
		for(int column=0;!found && column<5;column+=2)
		{
			if(grid[row][column]==square)
			{
				if(turn==1)				
					grid[row][column]='X';

				else 
					grid[row][column]='O';

				found=true;
			}
		}
	
}


void TicTac::set_turn()
{
	if(!check_winner())
	{
		if(turn==1)
		   turn= 2;	
		else
		   turn= 1;
	}
}


bool TicTac::check_winner()
{


	//Row Check
	for(int row=0; row<5; row+=2)
	{
		if(grid[row][0]==grid[row][2]&&grid[row][2]==grid[row][4])
					
			return true;		
	}

	//Column Check
	for(column=0; column<5; column+=2)
	{
		if(grid[0][column]==grid[2][column]&&grid[2][column]==grid[4][column])
					
			return true;		
	}


	//Diag Check
	if(  (grid[0][0]==grid[2][2]&&grid[2][2]==grid[4][4]) ||
	     (grid[0][4]==grid[2][2]&&grid[2][2]==grid[4][0])   )
				 
			return true;
	

	//Tie Check
	if(turn_counter==9)
	{			
		tie	 = true;
		return true;
	}

	return false;
}


char again()
{
	char choice;
	cout << "\n\n\n\tWould ye' like to try again? (Y/N): ";
	cin  >> choice;
        cin.ignore(1000,'\n');
	cout << endl << endl;

	return toupper(choice);
}


void TicTac::reset()
{
	int square_number = '1';

	for(int row=0;row<5;row+=2)
		for(int column=0;column<5;column+=2)

			grid[row][column]=square_number++;

	turn   = 1;	
	tie    = false;
	turn_counter = 0;
}

A short explanation with nothing additonal:

First, remember that arrays are zero based (in all dimensions), so the valid indiced for:
int array[3] are : array[0], array[1], and array[2]
and for
int grid[2][2] are : grid[0][0], grid[0][1], grid[1][0], and grid[1][1]

So, to quickly go through one index of an array, you can use a counter variable in a for loop:

Code:

for(int i = 0; i != ARRAY_LEN; ++i)
   array[i] = ...;

So, for a multidimensional array, you would have to nest loops (one for each dimension):

Code:

for(int i = 0; i != NUM_ROWS; ++i)
   for(int j = 0; j != NUM_COLS; ++j)
      grid[i][j] = ...;

So that, at each value of i in the range [0, NUM_ROWS - 1], the nested loop executes, looping j from 0 to NUM_COLS - 1.

Hope this clarifies things a little.

Cheers

I didn't expect for you to make the whole game.

i made this game like 3 months ago.. just offering my way of doing things. maybe you could learn something or ask questions or make suggestions or something.

learn == good