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Mr Darras has a boat, and he has to get his pet rabbit, dog, and Lion across the river without any of them eating each other. Knowing that the Lion will only eat the dog, the dog will only eat the rabbit, and the rabbit won't eat anyone, how can Mr Darras get them across safely.(Cannot put them in the boat together or keep them on shore together)
Take the dog over, come back and take the Lion over. Bring the dog back and take the rabbit over. Go back and get the dog!
All three are safe!