Two snakes of equal width are confined in a cage. One snake is long, the other is short. Your task is to design two escape passages, A and B, leading from the bottom of the cage, such that:
- The short snake can escape down passage A, but the long one cannot.
- The long snake can escape down passage B, but the short one cannot.
The passages must have no moving parts, trapdoors, or levers. Assume the snakes have circular cross-sections with the same diameter along their bodies. They can wiggle but cannot squeeze through passages narrower than their width.
This puzzle originally appeared in Kvantik Magazine in 2014. The solution will be provided at 5pm UK time. Please avoid posting spoilers in the comments.
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