What I don't get is: if the guards aren't to be trusted, how can the spies safel... | Hacker News

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		colanderman on Dec 21, 2010 \| parent \| context \| favorite \| on: The puzzle that started complexity theory. What I don't get is: if the guards aren't to be trusted, how can the spies safely tell them x? I suppose this is why public-key cryptography was invented ;)

nandemo on Dec 21, 2010 [–]

They can throw x away after using it. Alternatively, they can cross the y off their list after matching it (making it a one-time password).

The idea is that the guards aren't malicious, just stupid.

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