# Leetcode 841. Keys and Rooms

## DFS soluction

使用堆棧(stack)走訪無向圖

並使用 visited 陣列紀錄是否已經走訪過

如果 visited 陣列最後沒有 False 就代表房間全部走訪完畢

class Solution:
    def canVisitAllRooms(self, rooms: List[List[int]]) -> bool:
        visited = [False for i in range(len(rooms))]
        visited[0] = True
        stack = [0]

        while stack:
            room = stack.pop()
            keys = rooms[room]
            for key in keys:
                if not visited[key]:
                    stack.append(key)
                    visited[key] = True
        return all(visited)