program five_antennas
  implicit none
  integer :: a, e, k
  read(*,*) a
  read(*,*) e
  read(*,*) e
  read(*,*) e
  read(*,*) e
  read(*,*) k
  write(*,'(a)') trim(merge(":(  ","Yay!",e-a > k))
end program five_antennas