Treasure Finding For Pirates: Meet Witness-based Encryption

And so the pirates have got together and pooled their gold and doubloons and put them all into a treasure chest. Now they bury it at a secret location on Pirate Island. In order to hide the location, they create a puzzle to be solved, and if someone can solve it, they will find out the location of the treasure and win the booty.

And so the pirate leader — Long John Silver XXII — creates a difficult Sudoku puzzle:

He then posts the details of the locations on the grid for which to find details of the secret treasure location. Now the pirates scratch their heads, as they are good pirates but they are not so good at solving puzzles … “Shiver me timbers! I be ah pirate and I’m not ee puzzle solver”.

But the pirates know people in the Ye Olde Ship Inn who know how to solve puzzles. Unfortunately their “day rate” is five pieces of silver. So young Jim Lad XXII decides to ask one of the puzzle solvers for a quote, and is told that this type of puzzle will take two days to solve. And so Jim Lad thinks it is worth paying for the answer, and so, after two days, the puzzle solver reveals the answer, and Jim Lad claims his prize.