It's easy to see that this algorithm always works if the maze you're in has an entrance and an exit on its border.

很容易看出，如果迷宫的边界上有一个入口和一个出口，那么这种算法总是有效的。

youdao

I had it framed, and when I was reelected in 1982, it hung at the entrance to our bedroom so that I would see it every day.

我将它裱糊装框，1982年我重新当选州长时，我把它挂在卧室的入口处，每天都能看见。

youdao

He found a good place in a dark corner at the entrance to the car park. From here he could see everyone who was coming into the car park.

他在停车场进口的暗角处找好位置可以清楚看到进入停车场的每一个人。

youdao

But the one that they do now... I would be there to see when the wrestlers come in, at the back entrance.

但是他们现在做的这种……当摔跤手进来时，我会在后门那里看着。

麦迪逊广场花园 - SpeakingMax英语口语达人

Why, he was asked Tuesday by one MP, did he go in the back entrance to see David Cameron days after his election as prime minister rather than the front door, like heads of state?

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We may be grasping for straws here, but as the Sony PlayStation 3 now looks set for a late launch, perhaps the gaming console's entrance in the market this November, instead of this spring, will see a similarly sympathetic reception.

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You turn again to face the serene void of the court, and only then do you see the entrance doors of the Barnes Collection, in the second long building, directly parallel, across the way.

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