Keys and chests
Source: Kürschak 2010, problem 1
July 8, 2014
combinatorics unsolvedcombinatorics
Problem Statement
We have keys, each of them belonging to exactly one of locked chests. Our goal is to decide which key opens which chest. In one try we may choose a key and a chest, and check whether the chest can be opened with the key. Find the minimal number with the property that using tries, we can surely discover which key belongs to which chest.