Tic-Tac-Toe Check
Given a 3x3 tic-tac-toe board represented as an array of 3 strings, each string consisting of 3 characters from {'X', 'O', ' '} (empty), determine whether the board state is reachable in a valid game.
Given a 3x3 tic-tac-toe board represented as an array of 3 strings, each string consisting of 3 characters from {'X', 'O', ' '} (empty), determine whether the board state is reachable in a valid game.