implicit none
character(100) s
integer :: i,j,n
read *,s
n = len_trim(s)
i = scan(s(1:n),'C')
j = scan(s(1:n),'F')
if (i == 0 .or. j == 0 .or. j<i) then
   print '(a)','No'
else
   print '(a)','Yes'
endif
stop
end