import sys


line = sys.stdin.readline()
N, K = line.split(" ")
N = int(N)
K = int(K)
if N%2 == 0:
	if K <= (N/2):
		print("YES")
	else:
		print("NO")	
else:
	if K <= (N/2 + 1):
		print("YES")
	else:
		print("NO") import sys sys line = sys.stdin.readline() line sys.stdin.readline() sys.stdin.readline sys.stdin sys stdin readline N, K = line.split(" ") N line.split(" ") line.split line split " " K N = int(N) N int(N) int N K = int(K) K int(K) int K if N%2 == 0:
	if K <= (N/2):
		print("YES")
	else:
		print("NO")	
else:
	if K <= (N/2 + 1):
		print("YES")
	else:
		print("NO") N%2 == 0 N%2 N 2 0 if K <= (N/2):
		print("YES")
	else:
		print("NO")	 K <= (N/2) K N/2 N 2 print("YES") print "YES" print("NO") print "NO" if K <= (N/2 + 1):
		print("YES")
	else:
		print("NO") K <= (N/2 + 1) K N/2 + 1 N/2 N 2 1 print("YES") print "YES" print("NO") print "NO" N = int(N) int(N) N line = sys.stdin.readline() sys.stdin.readline() line K = int(K) int(K) K N, K = line.split(" ") line.split(" ") N K = line.split(" ") line.split(" ") K
import sys


line = sys.stdin.readline()
N, K = line.split(" ")
N = int(N)
K = int(K)
if N%2 == 0:
	if K <= (N/2):
		print("YES")
	else:
		print("NO")	
else:
	if K <= (N/2 + 1):
		print("YES")
	else:
		print("NO")