A very late entry for the knigh's travail. The solution can be found at: http://ruby.brian-schroeder.de/quiz/knights-travail/ It's just the standard dijkstra. regards, Brian -- http://ruby.brian-schroeder.de/ multilingual _non rails_ ruby based vocabulary trainer: http://www.vocabulaire.org/ | http://www.gloser.org/ | http://www.vokabeln.net/