How does the solver work?
Since Release 1.2, the solver has offered several strategies, each of which has been based upon the ‘Ariadne’s Thread’ technique. (In classical mythology, Theseus used the thread given by Ariadne in order to navigate the maze, constructed by Daedalus for King Minos of Crete, that housed the Minotaur – see Ovid’s Metamorphoses, Book VIII). When the solver finds itself stuck after a sequence of moves, it will retract moves (i.e. it will regather the thread) until it finds an alternative untried route.
