Alternative on the Island of Knights and Knaves

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An alternative is a person who alternatively tells the truth and a lie. That is, if his statement is true, his next statement is false. Once an alternative visited an island in which each inhabitant is either a "knight" or a "knave".


In this problem there are inhabitants, denoted by A, B, C, … . The alternative makes statements, and the problem is to infer who is a knight and who is a knave.


Contributed by: Izidor Hafner (December 2012)
Open content licensed under CC BY-NC-SA



The algorithm makes random statements about inhabitants and checks that the solution is unique. If after 50 attempts it fails, a message is returned.

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