def resolve():
    import math
    N, K = map(int, input().split())
    print("YES" if math.ceil(N/2) >= K else "NO")
resolve() def resolve():
    import math
    N, K = map(int, input().split())
    print("YES" if math.ceil(N/2) >= K else "NO") resolve import math math N, K = map(int, input().split()) N map(int, input().split()) map int input().split() ().split () input split K print("YES" if math.ceil(N/2) >= K else "NO") print "YES" if math.ceil(N/2) >= K else "NO" math.ceil(N/2) >= K math.ceil(N/2) math.ceil math ceil N/2 N 2 K "YES" "NO" resolve() resolve def resolve():
    import math
    N, K = map(int, input().split())
    print("YES" if math.ceil(N/2) >= K else "NO") def resolve():
    import math
    N, K = map(int, input().split())
    print("YES" if math.ceil(N/2) >= K else "NO") resolve
def resolve():
    import math
    N, K = map(int, input().split())
    print("YES" if math.ceil(N/2) >= K else "NO")
resolve()