algorithm - Generate a list of all unique Tic Tac Toe boards

Question

I would like to generate a text file containing all 19,683 Tic-Tac-Toe board layouts in the structure of 0 = Blank, 1 = X, and 2 = O. Unfortunately math is not my strong suit and I cannot seem to find any examples of this anywhere.

This isn't for homework I assure you. I intend to run this data through a Minimax calculator in order to generate an image that contains RGB values representing the optimal move based on the board setup. I am developing Tic-Tac-Toe for a platform that does not support functions (it's event-driven) so I will convert the board to a number in my game and then lookup the RGB of a pixel in an image which indicates what the best move is. It's a cheeky workaround, but one that requires no more RAM than an 145x145 pixel image (145x145 = 21,025 so each pixel represents the recommended move based on the board effectively). This also means I won't have to chew CPU time which is another plus.

Answer 1

There are 9 positions and an alphabet with 3 letters (X, O, empty). Total number of possible combinations is 3^9 = 19683.

for(int i = 0; i < 19683; ++i)
{
    int c = i;
    for (int j = 0; j < 9; ++j)
    {
        cout << (c % 3) << " ";
        c /= 3;
    }

    cout << endl;
}