class Solution:
    def validTicTacToe(self, board: List[str]) -> bool:
        NumO = 0
        NumX = 0

        for i in range(3):
            for j in range(3):
                NumO += (board[i][j] == 'O')
                NumX += (board[i][j] == 'X')

        if NumX < NumO or NumX > NumO + 1:
            return False

        Dir = [[0,1], [1, 0], [1, 1], [-1,1]]

        def helper(x0, y0, Player):

            for dir in Dir:
                x = x0
                y = y0
                for step in range(2):
                    x += dir[0]
                    y += dir[1]

                    if (0 <= x < 3 and 0 <= y < 3 and board[x][y] == Player):
                        if step == 1:
                            return True
                    else:
                        break

            return False

        BoolX = False
        BoolO = False

        for i in range(3):
            for j in range(3):
                if board[i][j] == 'X': 
                    BoolX = BoolX or helper(i, j, 'X')
                if board[i][j] == 'O':
                    BoolO = BoolO or helper(i, j, 'O')

        if BoolX and BoolO:
            return False

        if BoolX:
            if NumX == NumO:
                return False

        if BoolO:
            if NumX > NumO:
                return False

        return True