Six friends M, N, O, P and R, study in the same class, live in the same building but on different floors. The ground floor is numbered as the first floor, the floor above it as the second floor and so on while the other floors are numbered till the topmost floor is numbered as the sixth floor. P lives two floors above the floor of M, who lives three floors above the floor of Q. R does not live above or below the floor of M. On which floor does R live?