Optimal play in 'Guess Who?'
David Cushing, Stuart Gipp, Ezra Levick, Em Rickinson, David I. Stewart
TL;DR
An optimal strategy for the children's game Guess Who?
Abstract
We prove an optimal strategy for the children's game Guess Who? assuming the official rules are in use and that both players ask `classical' questions with a bipartite response. Applying a technique described in [Rabern, B \& Rabern, L 2008, 'A simple solution to the hardest logic puzzle ever', \textit{Analysis}, vol. 68, no. 2, pp.~105-112.] allows for questions with tripartite responses; we explain this innovation and give an optimal strategy for two players applying it.
