def main():
    N,K = map(int,input().split())
    if N%2==0:
        pass
    else:
        N += 1
    
    if K<=N//2:
        print("YES")
    else:
        print("NO")
if __name__ == '__main__':
    main() def main():
    N,K = map(int,input().split())
    if N%2==0:
        pass
    else:
        N += 1
    
    if K<=N//2:
        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 if N%2==0:
        pass
    else:
        N += 1
    
     N%2==0 N%2 N 2 0 N += 1 N 1 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 __name__ == '__main__':
    main() __name__ == '__main__' __name__ '__main__' main() main def main():
    N,K = map(int,input().split())
    if N%2==0:
        pass
    else:
        N += 1
    
    if K<=N//2:
        print("YES")
    else:
        print("NO") def main():
    N,K = map(int,input().split())
    if N%2==0:
        pass
    else:
        N += 1
    
    if K<=N//2:
        print("YES")
    else:
        print("NO") main
def main():
    N,K = map(int,input().split())
    if N%2==0:
        pass
    else:
        N += 1
    
    if K<=N//2:
        print("YES")
    else:
        print("NO")
if __name__ == '__main__':
    main()