* Search.hs Simple search type class (see Fig. 2 in the paper) * SearchStrat.hs Extendsion of search type class by search strategy parameter for the functions space and solutions (see Fig. 4 in the paper) * Zurg.hs Implementation of the Zurg riddle using the simple search type class (see Fig. 3 in the paper) * ZurgStrat.hs Implementation of the Zurg riddle using the extended search type class * zurg.pl Prolog implementation of the Zurg riddle * ZurgDirect.hs Direct implementation of the Zurg riddle without using the type class.