import sys
def input(): return sys.stdin.readline().strip()

def resolve():
    n,k=map(int, input().split())
    num=-(-n // 2)
    if num<k:
        print('NO')
    else:
        print('YES')
resolve() import sys sys def input(): return sys.stdin.readline().strip() input def resolve():
    n,k=map(int, input().split())
    num=-(-n // 2)
    if num<k:
        print('NO')
    else:
        print('YES') resolve n,k=map(int, input().split()) n map(int, input().split()) map int input().split() ().split () input split k num=-(-n // 2) num -(-n // 2) -n // 2 -n n 2 if num<k:
        print('NO')
    else:
        print('YES') num<k num k print('NO') print 'NO' print('YES') print 'YES' resolve() resolve def input(): return sys.stdin.readline().strip() def input(): return sys.stdin.readline().strip() input def resolve():
    n,k=map(int, input().split())
    num=-(-n // 2)
    if num<k:
        print('NO')
    else:
        print('YES') def resolve():
    n,k=map(int, input().split())
    num=-(-n // 2)
    if num<k:
        print('NO')
    else:
        print('YES') resolve
import sys
def input(): return sys.stdin.readline().strip()

def resolve():
    n,k=map(int, input().split())
    num=-(-n // 2)
    if num<k:
        print('NO')
    else:
        print('YES')
resolve()