IMPLICIT NONE
INTEGER :: N, I
CHARACTER,DIMENSION(100) :: C
LOGICAL :: P = .false. , W = .false. , G = .false. , Y = .false.

READ*, N
READ*, C(1:N)

DO I = 1, N   
    IF ( C(I) == "P") THEN
        P = .true.
    ELSE IF (C(I) == "W") THEN
        W = .true.
    ELSE IF (C(I) == "G") THEN
        G = .true.
    ELSE IF (C(I) == "Y") THEN
        Y = .true.
    END IF
END DO

IF (P .AND. W .AND. G .AND. Y) THEN
    PRINT*, "Four"
ELSE
    PRINT*, "Three"
END IF
 
END