Move, pour, cross: the classic logic puzzles

There are 100 levels of three classic state puzzles: the tower of Hanoi, water jugs, and getting everyone across a river without leaving something to be eaten.

Every level shows the best possible number of moves. You solve the level by reaching the goal at all; matching that number is the harder game on top.

Yes, and that is measured rather than assumed. Each level was run through a breadth-first search offline, and a configuration only becomes a level if the search found a way through. The same search is where the best possible number comes from.

Because the other two families are small and that is a property of the puzzles, not of the generator. Playable towers run from 3 to 9 discs, which is 11 distinct levels. Of 132 river configurations tested, 64 have no solution at all and 34 are over in fewer than five moves; only seven distinct shapes are both solvable and worth playing. The jugs, on the other hand, give 287 combinations of capacities and targets with a measured minimum from 4 to 22 moves.

Because the illegal move is the part that teaches the puzzle. Losing the whole level for it would mean replaying fifteen correct moves to pay for one wrong one.

The furthest level you solved is kept in your own browser. There is no account and nothing is sent anywhere.