You are going home with your dog, hen and corn. On the way, you find a river.
A small boat is there, you have to take all your items across the river.
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The boat is very small so you can carry only one thing (or none) with you at a time.
You can't leave the dog with the hen. (dogs eat hens)
You can't leave the hen with the corn. (hens eat corns)
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