Noughts and crosses

Tic-tac-toe or Noughts and crosses is a world-wide known classical strategy game, and it is basically
a paper-and-pencil game. The game is designed for two players that are alternately entering the X
and O symbols into the empty fields on a 3x3 grid. Each of two players uses only one of these two
symbols. Player that plays first usually takes the X symbol. The winner is the first player that gets
three of his marks in a row (horizontally, vertically or diagonally)