expert Set 69 Logic Puzzle

Expert River Crossing Puzzle #69

Show solution

[{"trip":1,"direction":"\u2192","carrying":["Goat"],"leftBank":["Wolf","Cabbage"],"rightBank":["Goat"],"note":"Take the goat first."},{"trip":2,"direction":"\u2190","carrying":[],"leftBank":["Wolf","Cabbage","Farmer"],"rightBank":["Goat"],"note":"Return empty."},{"trip":3,"direction":"\u2192","carrying":["Wolf"],"leftBank":["Cabbage"],"rightBank":["Goat","Wolf"],"note":"Take the wolf."},{"trip":4,"direction":"\u2190","carrying":["Goat"],"leftBank":["Cabbage","Goat"],"rightBank":["Wolf"],"note":"Bring goat back."},{"trip":5,"direction":"\u2192","carrying":["Cabbage"],"leftBank":["Goat"],"rightBank":["Wolf","Cabbage"],"note":"Take the cabbage."},{"trip":6,"direction":"\u2190","carrying":[],"leftBank":["Goat","Farmer"],"rightBank":["Wolf","Cabbage"],"note":"Return empty."},{"trip":7,"direction":"\u2192","carrying":["Goat"],"leftBank":[],"rightBank":["Wolf","Cabbage","Goat"],"note":"Take goat. Done!"}]

Title
Expert River Crossing Puzzle #69
Scenario
Wolf, Goat & Cabbage
Narrative
A farmer must cross a river with a wolf, a goat, and a cabbage. The boat can carry only the farmer and one other passenger.
Entities
  • {"id":"wolf","name":"Wolf","icon":"\ud83d\udc3a"}
  • {"id":"goat","name":"Goat","icon":"\ud83d\udc10"}
  • {"id":"cabbage","name":"Cabbage","icon":"\ud83e\udd6c"}
BoatCapacity
1
Constraints
  • The wolf cannot be left alone with the goat.
  • The goat cannot be left alone with the cabbage.
Question
Describe a valid sequence of crossings that gets everyone to the other side without violating any constraint. What is the minimum number of trips required?
Solution
  • {"trip":1,"direction":"\u2192","carrying":["Goat"],"leftBank":["Wolf","Cabbage"],"rightBank":["Goat"],"note":"Take the goat first."}
  • {"trip":2,"direction":"\u2190","carrying":[],"leftBank":["Wolf","Cabbage","Farmer"],"rightBank":["Goat"],"note":"Return empty."}
  • {"trip":3,"direction":"\u2192","carrying":["Wolf"],"leftBank":["Cabbage"],"rightBank":["Goat","Wolf"],"note":"Take the wolf."}
  • {"trip":4,"direction":"\u2190","carrying":["Goat"],"leftBank":["Cabbage","Goat"],"rightBank":["Wolf"],"note":"Bring goat back."}
  • {"trip":5,"direction":"\u2192","carrying":["Cabbage"],"leftBank":["Goat"],"rightBank":["Wolf","Cabbage"],"note":"Take the cabbage."}
  • {"trip":6,"direction":"\u2190","carrying":[],"leftBank":["Goat","Farmer"],"rightBank":["Wolf","Cabbage"],"note":"Return empty."}
  • {"trip":7,"direction":"\u2192","carrying":["Goat"],"leftBank":[],"rightBank":["Wolf","Cabbage","Goat"],"note":"Take goat. Done!"}
MinimumTrips
7
Hint
No hints are provided for this difficulty. Find the full solution on your own.
PartialSolutionHint