There are two kinds of people living on an island. One is the truth-teller and the other is the lie-teller. One day, one person travels to the island and encounters three islanders A. B, and C. Then he asked them who was the truth-teller and who was the lie-teller. A said, "B and C are both lie-tellers. " B said, "I am the truth-teller. " C said, "B is a lie-teller. ". How many of these three people are telling lies? ['.', '.', '.', '.']