Coming to Agreement, a logic puzzle for Oxford admissions interviews

Re:Coming to Agreement, a logic puzzle for Oxford admissions... by kthejoker2 on Tuesday December 28, 2021 @05:04AM (#29712154)

Literal collision variation:

You are walking down one side of a hallway. It is only wide enough for two people to pass side by side.

Due to shoddy logic puzzle-appropriate workmanship, the hallway lights only work when nobody in the hallway is moving, and otherwise it is complete darkness.

A person is coming in the opposite direction, on the same side as you.

As a logician you are far too shy to be able to speak to this other person directly.

How do you avoid colliding with them?

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Re:Coming to Agreement, a logic puzzle for Oxford admissions... by BoiledCabbage on Tuesday December 28, 2021 @11:22AM (#29715111)

Pretty simple because time isn't discrete in this puzzle.

Assuming they are logical as well, both of you know you can't keep walking forward in the dark without risking bumping. If you change sides, they could as well. So you both stop waking and the lights turn on.

Because you both know time isn't discrete, if the lights go out and you weren't moving, then it was your partner that was moving. The person who initiates the darkness gets to move. Wait a random amount of time and if the lights didn't go out, swap sides of the hallway.

Once the swap is done (by the one who moved first) and you both see you are no longer going to collide, both resume waking forward.

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Re:Coming to Agreement, a logic puzzle for Oxford admissions... by Something1234 on Tuesday December 28, 2021 @12:50PM (#29716059)

Take out my phone and turn on my flashlight, so they can see me. Also hug the right wall, cause that's what most people do.

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Re:Coming to Agreement, a logic puzzle for Oxford admissions... by themarlzy on Wednesday December 29, 2021 @01:41AM (#29722542)

Unless you had me - in Australia we’d veer left

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