计算一个环形街道上的房屋数量

This solution uses a two-pass method on a circular street abstraction. Initially, the solution assumes an arbitrary starting point on the street and opens 'k' consecutive doors to the left (creating a unique pattern or a marker). Then, it iterates through the street starting from the first open door encountered, counting each house as it proceeds. It moves left and closes each door as it goes, until it encounters a closed door, indicating it has returned to the start point and therefore has counted all houses.

时间复杂度: O(n)

空间复杂度: O(1)

# Definition for a street.
# class Street:
#     def openDoor(self):
#         pass
#     def closeDoor(self):
#         pass
#     def isDoorOpen(self):
#         pass
#     def moveRight(self):
#         pass
#     def moveLeft(self):
#         pass

class Solution:
    def houseCount(self, street: Optional['Street'], k: int) -> int:
        # Open k doors to the left to mark the start
        for i in range(k):
            street.openDoor()
            street.moveLeft()
        
        # Initialize house count
        n=0
        # Loop until an unopened door is found
        while street.isDoorOpen():
            n+=1  # Increment house count
            street.closeDoor()  # Close the door behind
            street.moveLeft()  # Move to the next house
        return n