Guess the fourth person
The population of an Island consists of only two types of people, the Knights who tell the truth and Knaves who always lie.
One day a man from another country came to that place and met four habitants.
He asked the first one whether the second one is a knight or a knave.
The reply was knave.
Similarly the second habitant said the the third one is a knave.
The third said the same about the fourth.
Who is the fourth habitant knight or knave?