def func():
    pass


def main():
    n, k = map(int, input().split())

    mx = (n + 1) // 2
    if mx >= k:
        print("YES")
    else:
        print("NO")


if __name__ == '__main__':
    main() def func():
    pass func def main():
    n, k = map(int, input().split())

    mx = (n + 1) // 2
    if mx >= k:
        print("YES")
    else:
        print("NO") main n, k = map(int, input().split()) n map(int, input().split()) map int input().split() ().split () input split k mx = (n + 1) // 2 mx (n + 1) // 2 n + 1 n 1 2 if mx >= k:
        print("YES")
    else:
        print("NO") mx >= k mx k print("YES") print "YES" print("NO") print "NO" if __name__ == '__main__':
    main() __name__ == '__main__' __name__ '__main__' main() main def func():
    pass def func():
    pass func def main():
    n, k = map(int, input().split())

    mx = (n + 1) // 2
    if mx >= k:
        print("YES")
    else:
        print("NO") def main():
    n, k = map(int, input().split())

    mx = (n + 1) // 2
    if mx >= k:
        print("YES")
    else:
        print("NO") main
def func():
    pass


def main():
    n, k = map(int, input().split())

    mx = (n + 1) // 2
    if mx >= k:
        print("YES")
    else:
        print("NO")


if __name__ == '__main__':
    main()
