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Locks and keys: How fast can you open several locks with too many keys?

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 نشر من قبل Olivier Marchal
 تاريخ النشر 2015
  مجال البحث الهندسة المعلوماتية
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 تأليف Olivier Marchal




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This short note is the result of a French Hippocampe internship that aims at introducing the world of research to young undergraduate French students. The problem studied is the following: imagine yourself locked in a cage barred with $n$ different locks. You are given a keyring with $N geq n$ keys containing the $n$ keys that open the locks. In average, how many trials are required to open all locks and get out? The article studies $3$ different strategies and compare them. Implementation of the strategies are also proposed as illustrations of the theoretical results.



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