python.py

class Solution:
    def __init__(self):
        self.visited = {}
    def startWalking(self, heights: List[List[int]], i: int, j: int):
        self.visited = {}
        up_left =  self.walkThroughMatrix(heights, i, j, up_left=True)
        self.visited = {}
        down_right = self.walkThroughMatrix(heights, i, j, up_left=False)
        return up_left and down_right
    
    def walkThroughMatrix(self, heights: List[List[int]], i: int, j: int, prev_height=100_001, up_left=True) -> bool:
        if up_left:
            if i < 0 or j < 0:
                return True
            if i >= len(heights) or j >= len(heights[0]):
                return False
        else:
            if i < 0 or j < 0:
                return False
            if i >= len(heights) or j >= len(heights[0]):
                return True
        if heights[i][j] > prev_height:
            return False
        if (i, j) in self.visited:
            return False
        self.visited[(i, j)] = 1
        return self.walkThroughMatrix(heights, i - 1, j, heights[i][j], up_left=up_left) or \
            self.walkThroughMatrix(heights, i, j - 1, heights[i][j], up_left=up_left) or \
            self.walkThroughMatrix(heights, i + 1, j, heights[i][j], up_left=up_left) or \
            self.walkThroughMatrix(heights, i, j + 1, heights[i][j], up_left=up_left)
        

    def pacificAtlantic(self, heights: List[List[int]]) -> List[List[int]]:
        can = list()
        for i in range(len(heights)):
            for j in range(len(heights[0])):
                if self.startWalking(heights, i, j):
                        can.append([i, j])
        return can