题解 | Python3 | 高可读性一看就会版

#
# 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
#
#
# @param matrix char字符型二维数组
# @param word string字符串
# @return bool布尔型
#

# global def
X = 0
Y = 1

class Solution:
    def hasPath(self, matrix: List[List[str]], word: str) -> bool:
        # write code here
        if not matrix or not word:
            return False
        # init
        self.__size = len(matrix[0]), len(matrix)
        self.__target = word
        self.__matrix = matrix
        self.__visited = [[False for _ in range(self.__size[X])] for _ in range(self.__size[Y])]
        # prog
        for ix in range(self.__size[X]):
            for iy in range(self.__size[Y]):
                if self.tryFindPath((ix, iy), 0):
                    return True
        return False


    def tryFindPath(self, pos: tuple, idxof_target: int) -> bool:
        # all word is match successfully
        if idxof_target >= len(self.__target):
            return True
        # else word is not fully match , require continue:

        # x: out of matrix
        if self.positionOutOfRange(pos):
            return False

        # x: already visited
        if self.__visited[pos[Y]][pos[X]]:
            return False

        # x: word not match
        curr_match_word = self.__target[idxof_target]
        if self.__matrix[pos[Y]][pos[X]] != curr_match_word:
            return False

        # √: when execute here, current word is successfully matched.
        print(f"√: matched {curr_match_word} in {pos}")
        self.__visited[pos[Y]][pos[X]] = True

        # next step, we try to match next word:
        if (
            (self.tryFindPath((pos[X] + 1, pos[Y]), idxof_target + 1)) or 
            (self.tryFindPath((pos[X] - 1, pos[Y]), idxof_target + 1)) or 
            (self.tryFindPath((pos[X], pos[Y] + 1), idxof_target + 1)) or 
            (self.tryFindPath((pos[X], pos[Y] - 1), idxof_target + 1))
        ): 
            return True
        else:
            self.__visited[pos[Y]][pos[X]] = False
            return False


    def positionOutOfRange(self, case_pos: tuple) -> bool:
        if case_pos[X] < 0 or case_pos[Y] < 0:
            return True
        if case_pos[X] >= self.__size[X] or case_pos[Y] >= self.__size[Y]:
            return True
        return False