Sort demands a unique ordering, which isn't present in your case. You're constructing an Eulerian path. See Fleury's algorithm:
http://en.wikipedia.org/wiki/Eulerian_path -- http://mail.python.org/mailman/listinfo/python-list
Sort demands a unique ordering, which isn't present in your case. You're constructing an Eulerian path. See Fleury's algorithm:
http://en.wikipedia.org/wiki/Eulerian_path -- http://mail.python.org/mailman/listinfo/python-list