#include <iostream>

using namespace std;

/* The exact same code, but now implementing arrays for convenience.
*  While I discourage hard coding, I don't mind it in this case because
*  a tic-tac-toe grid is always fixed to be a 3x3 grid. If it were
*  meant to be expandable, then you'd have to avoid hard coding.
*/

int turn = 0, place;
bool Xwin = false, Owin = false, invalid_input = false;
string pos = "         ";	// 9 spaces, one for each grid
// char arrays are strings, but access them by the index
/*
 * 0 1 2	User Indicies: 1 2 3
 * 3 4 5		       4 5 6
 * 6 7 8		       7 8 9
 */
char input_char;

int main()
{
	while(!Xwin && !Owin && turn < 9)
	{
		for(int i = 0; i < 7; i++)	// 7 rows needed for grid
		{	// Only odd rows contain X and O marks
			if(i % 2 == 0)
				cout << "+---+---+---+" << endl;
			else
				cout << "| " << pos[i*3/2 - 1]
				     << " | " << pos[i*3/2]
				     << " | " << pos[i*3/2 + 1]
				     << " |" << endl;
		}

		if(turn % 2 == 0)
			input_char = 'X';
		else
			input_char = 'O';

		do
		{
			cout << "Place " << input_char << " at: ";
			cin >> place;
			cin.ignore();

			if(place < 1 || place > 9)
			{
				invalid_input = true;
				cout << "Invalid input! 1-9 only.\n";
			}
			else	// An entire switch-case reduced to one line!
				invalid_input = (pos[place-1] != ' ');
			
			if(invalid_input)
				cout << "Invalid input! Position already filled.\n";

		} while(invalid_input);

		// Another entire switch-case reduced to one line using arrays!
		pos[place-1] = input_char;

		if(turn >= 4)
		{
			// Row based victory
			for(int i = 0; i < 3; i++)
				if(pos[i*3] == pos[i*3+1] && pos[i*3+1] == pos[i*3+2])
				{
					if(pos[i*3] == 'X')
						Xwin = true;
					else if(pos[i*3] == 'O')
						Owin = true;
				}
			// Column based victory
			for(int i = 0; i < 3; i++)
				if(pos[i] == pos[(i+1)*3] && pos[(i+1)*3] == pos[(i+2)*3])
				{
					if(pos[i] == 'X')
						Xwin = true;
					else if(pos[i] == 'O')
						Owin = true;
				}
			// Diagonal based victory
			for(int i = 2; i <= 4; i += 2)
				if(pos[4] == pos[4-i] && pos[4] == pos[4+i])
				{
					if(pos[i] == 'X')
                                                Xwin = true;
                                        else if(pos[i] == 'O')
                                                Owin = true;
				}
		}
		turn++;

	}

	// Display the final results
	for(int i = 0; i < 7; i++)	// Print the grid one more time
                {       
                        if(i % 2 == 0)
                                cout << "+---+---+---+" << endl;
                        else
                                cout << "| " << pos[i*3/2 - 1]
                                     << " | " << pos[i*3/2]
                                     << " | " << pos[i*3/2 + 1]
                                     << " |" << endl;
                }

	cout << "Game Over - ";
	if(Xwin)
		cout << "X wins!" << endl;
	else if(Owin)
		cout << "O wins!" << endl;
	else
		cout << "Draw" << endl;

	return 0;
}