Question: I know about alpha-beta pruning and the minimax algorithm.  

What other algorithms would you suggest?

Is it possible if we use negascout?

Answer: 
Considering the simplicity of the game the optimum moves can be simply stored.

Relevant XKCD-
[![](https://imgs.xkcd.com/comics/tic_tac_toe.png)](http://xkcd.com/832/)
Tic-Tac-Toe's entire game tree can be represented in memory, so you can just generate that and backtrack winning moves. There are less than 363k legal configurations.