Question: you are on an island inhabited by 3 types of...
You are on an island inhabited by 3 types of people. Those who only tell the truth (knights), those who only tell lies (knaves) and those who either tell the truth or lie (spies). You come across 3 people. You know that one is a knight, one is a knave and one is a spy.
A says B is a spy
B says C is a spy
C says B is a spy
What type is each person