Tic-Tac-Toe: How to populate decision tree?

Question

I'm making a Tic-Tac-Toe program. I plan to use minimax with it. I made a tree with space for all possible game sequences and I'm looking for a way to populate it. I currently have this type:

typedef struct name
{
    char grid [3] [3];
    struct name * child [9];
} node;

and I'm looking for a way to fill grid just like it's shown here. How would I go filling the grid to make sure that all possible combinations are there? My plan is to have the game recognize every move player can take and then decide what steps to take in order to win (I still need to figure out the decision part, but I'm holding that until I can fill the grids in tree).

Answer 1

Sounds like a prime candidate for recursion to me...