One-way roads
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Revision as of 09:40, 19 August 2012 by Oscarlevin (talk | contribs)
Found this one on the SUNY Stony Brook Math Problem of the Month archives.
Puzzle
A county has n > 4 cities. Is it possible to connect some pairs of cities by one-way roads so that one can travel from every city to every other city using only one or two roads? If so, how? Note that for every pair of cities A and B, only one road connecting A with B is allowed; this road leads from A to B or from B to A, but not both ways.
