def exist(self, board, word):
        """
        :type board: List[List[str]]
        :type word: str
        :rtype: bool
        """
        check_board = [[True] * len(board[0]) for _ in range(len(board))]
        for i in range(len(board)):
            for j in range(len(board[0])):
                if board[i][j] == word[0] and check_board:
                    check_board[i][j] = False
                    res = self.check_exist(check_board, board, word, 1, len(word), i, j)
                    if res:
                        return True
                    check_board[i][j] = True
        return False

        :type board: List[List[str]]
        :type word: str
        :rtype: bool
        
python/079_Word_Search.py