N, K = map(int, input().split())
if N / 2 + 1 > K:
  print("YES")
elif N / 2 + 1 == K:
  if N % 2 != 0:
    print("YES")
  else:
    print("NO")
else:
  print("NO") N, K = map(int, input().split()) N map(int, input().split()) map int input().split() ().split () input split K if N / 2 + 1 > K:
  print("YES")
elif N / 2 + 1 == K:
  if N % 2 != 0:
    print("YES")
  else:
    print("NO")
else:
  print("NO") N / 2 + 1 > K N / 2 + 1 N / 2 N 2 1 K print("YES") print "YES" elif N / 2 + 1 == K:
  if N % 2 != 0:
    print("YES")
  else:
    print("NO") N / 2 + 1 == K N / 2 + 1 N / 2 N 2 1 K if N % 2 != 0:
    print("YES")
  else:
    print("NO") N % 2 != 0 N % 2 N 2 0 print("YES") print "YES" print("NO") print "NO" print("NO") print "NO" N, K = map(int, input().split()) map(int, input().split()) N K = map(int, input().split()) map(int, input().split()) K
N, K = map(int, input().split())
if N / 2 + 1 > K:
  print("YES")
elif N / 2 + 1 == K:
  if N % 2 != 0:
    print("YES")
  else:
    print("NO")
else:
  print("NO")