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