One Seat in the Boat

The wolf, goat and cabbage river crossing as a story - seven crossings, one backward move.

A farmer must ferry a wolf, a goat and a sack of cabbages across a river in a boat that holds him plus one passenger. Left unsupervised, the wolf eats the goat and the goat eats the cabbages; the wolf has no interest in cabbage. He may cross as often as he likes in either direction. The story asks how he gets all three across intact. You lock in a guess, then step through the answer and breakdown.

Why quant interviews test this

As an interview question this is a state-space search in disguise: interviewers listen for the invariant, the goat never unsupervised with anything, and a memorised sequence does not show it. The written solution is at /brain-teasers/river-crossing/solution.

The One Seat in the Boat guide covers how scoring works, the strategy that wins, a worked example and the mistakes most players make.

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