Transport puzzle
Transport puzzles are logistical puzzles, hence are puzzles which represent real-life transport problems.
Like in shuffling puzzles, no piece is ever lost or added to the board.
In contrast to shuffling puzzles, however, in transport puzzles all tokens have to follow certain routes given on the board; they cannot be lifted off the board and placed on faraway positions that have no visible connection to the from-position.
Hence transport puzzles often mean that the player has to move (physical) objects in a very restricted space.
This puzzle class has several subclasses:
- sokoban puzzles
- sliding puzzles
- with Samuel Loyds fifteen puzzle as the most well known example
- train shunting puzzles
- river cross puzzles - see below
A well known example:
A farmer has a boat, a cabbage, a goat and a wolf. He has to cross the river with his boat. His boat is small, so he can take either the cabbage, the goat or the wolf with him - but not two of them at the same time. If he leave the goat with the cabbage unattended, the goat will eat it. Likewise, he cannot leave the goat with the wolf alone.
How many crossings must the farmer make?
The famous British puzzler Henry Dudeney added several puzzles to this category.