PROGRAM ATCODER

implicit none
integer :: n,k,check

read(*,*) n,k

check = n/2
if (mod(n,2) /= 0) then
	check = check +1
end if

if (check >= k) then
	write(*,'(a)') 'YES'
else
	write(*,'(a)') 'NO'
end if

END PROGRAM ATCODER
