The pirate puzzle asks how a crew of pirates might fairly divide a pile of gold coins when each pirate votes and the most senior pirate proposes the split. It's a classic logic riddle that tests strategic thinking and backward induction.
Start by imagining the smallest group: if only one pirate remains, they take all the coins. With two pirates, the senior pirate must offer something to get a vote — otherwise the junior will reject and end up with everything. Work backward through larger crews, remembering that each pirate prefers survival first, coins second, and enjoys tossing others overboard third.
A useful shortcut is to label pirates A (senior), B, C, etc., and calculate who gets what by checking which pirates would be worse off if the proposal fails. Bribe the minimum number of pirates needed by offering them as little as possible while ensuring they prefer the offer to the alternative.
For example, with five pirates and 100 coins, Pirate A can secure victory by buying the cheapest votes: offer 1 coin to exactly the pirates who would get nothing in the next round, keep the rest, and survive. The exact split depends on the number of pirates and total coins, but the strategy—work backward and pay the minimal bribes—always solves it.
If you want, I can walk through a full numeric example step-by-step for a specific crew size and coin total. Try one yourself and see whether your result matches the backward-induction method!
Start by imagining the smallest group: if only one pirate remains, they take all the coins. With two pirates, the senior pirate must offer something to get a vote — otherwise the junior will reject and end up with everything. Work backward through larger crews, remembering that each pirate prefers survival first, coins second, and enjoys tossing others overboard third.
A useful shortcut is to label pirates A (senior), B, C, etc., and calculate who gets what by checking which pirates would be worse off if the proposal fails. Bribe the minimum number of pirates needed by offering them as little as possible while ensuring they prefer the offer to the alternative.
For example, with five pirates and 100 coins, Pirate A can secure victory by buying the cheapest votes: offer 1 coin to exactly the pirates who would get nothing in the next round, keep the rest, and survive. The exact split depends on the number of pirates and total coins, but the strategy—work backward and pay the minimal bribes—always solves it.
If you want, I can walk through a full numeric example step-by-step for a specific crew size and coin total. Try one yourself and see whether your result matches the backward-induction method!