Putnam 2002 B2
- Session B
Consider a polyhedron with at least five faces such that exactly three edges emerge from each of its vertices. Two players play the following game:
Each player, in turn, signs his or her name on a previously unsigned face. The winner is the player who first succeeds in signing three faces that share a common vertex.
Show that the player who signs first will always win by playing as well as possible.
Curated text Kedlaya Putnam archive. Quoted with source.
Solutions
Human solution Solution 1 by Kiran Kedlaya and Lenny Ng
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