Suppose that you encounter 4 people, each of whom is either a truth teller (always tells the truth), a liar (always tell lies), a random answerer (always answer randomly with 'Yes' or 'No'), or an alternator. The alternator, upon being asked the first question, will randomly choose to be a truth teller, a liar, or a random answerer and then answer the question with that persona. Every time the alternator is asked a question thereafter, he'll switch his current persona in the following cycle: truthteller -> liar -> random answerer -> truth teller ..., etc. For instance, if the alternator acted as a truth teller for a particular question, he will act as a liar when he is asked the next question, and as a random answerer the question after that.

You know that in this group of 4, there are 1 random answerer, 1 truth teller, 1 liar, and 1 alternator, but you don't know which person is which. The puzzle is to identify the 1 random answerer with the following information:

1) You can only ask yes/no questions to 1 person at a time

2) You can ask the same question of different people, or address different questions to the same person.

3) You can not ask any question which is impossible for a truth teller/liar to answer with a yes/no (ie. asking a truth teller what a random answerer would say to a particular question, asking paradoxes, etc. )

4) Each person in the group of 4 knows what type of people the remaining 3 are.

Determine a strategy that is guaranteed to find the 1 random answerer in 8 questions or less.

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## bushindo 14

Suppose that you encounter 4 people, each of whom is either a truth teller (always tells the truth), a liar (always tell lies), a random answerer (always answer randomly with 'Yes' or 'No'), or an alternator. The alternator, upon being asked the first question, will randomly choose to be a truth teller, a liar, or a random answerer and then answer the question with that persona. Every time the alternator is asked a question thereafter, he'll switch his current persona in the following cycle: truthteller -> liar -> random answerer -> truth teller ..., etc. For instance, if the alternator acted as a truth teller for a particular question, he will act as a liar when he is asked the next question, and as a random answerer the question after that.

You know that in this group of 4, there are 1 random answerer, 1 truth teller, 1 liar, and 1 alternator, but you don't know which person is which. The puzzle is to identify the 1 random answerer with the following information:

1) You can only ask yes/no questions to 1 person at a time

2) You can ask the same question of different people, or address different questions to the same person.

3) You can not ask any question which is impossible for a truth teller/liar to answer with a yes/no (ie. asking a truth teller what a random answerer would say to a particular question, asking paradoxes, etc. )

4) Each person in the group of 4 knows what type of people the remaining 3 are.

Determine a strategy that is guaranteed to find the 1 random answerer in 8 questions or less.

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