Bah. In case you don't figure it out, "module Dijkstra" is meant to be on it's own line. Hopefully the cut/paste job didn't mangle anything else. ie. # # requires the implementation of an each_neighbour method which must yield the neighbours of an object, and optionally the 'cost' of the link. # it doesn't require the full object list - it builds the list as it goes. Would probably be faster if it had the whole list, but I wanted to keep the # code generic # module Dijkstra class Vertex attr_reader :object .. etc ... -----Original Message----- From: Daniel Sheppard Sent: Tuesday, 30 August 2005 6:05 PM To: 'ruby-talk / ruby-lang.org' Subject: [SOLUTION] Word Chains (#44) ##################################################################################### This email has been scanned by MailMarshal, an email content filter. #####################################################################################