import sys
sys.setrecursionlimit(10 ** 5 + 10)
def input(): return sys.stdin.readline().strip()

def resolve():
    
    N,K=map(int,input().split())
    print('YES' if -(-N//2)>=K else 'NO')
    
resolve() import sys sys sys.setrecursionlimit(10 ** 5 + 10) sys.setrecursionlimit sys setrecursionlimit 10 ** 5 + 10 10 ** 5 10 5 10 def input(): return sys.stdin.readline().strip() input def resolve():
    
    N,K=map(int,input().split())
    print('YES' if -(-N//2)>=K else 'NO')
     resolve N,K=map(int,input().split()) N map(int,input().split()) map int input().split() ().split () input split K print('YES' if -(-N//2)>=K else 'NO') print 'YES' if -(-N//2)>=K else 'NO' -(-N//2)>=K -(-N//2) -N//2 -N N 2 K 'YES' 'NO' 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())
    print('YES' if -(-N//2)>=K else 'NO')
     def resolve():
    
    N,K=map(int,input().split())
    print('YES' if -(-N//2)>=K else 'NO')
     resolve
import sys
sys.setrecursionlimit(10 ** 5 + 10)
def input(): return sys.stdin.readline().strip()

def resolve():
    
    N,K=map(int,input().split())
    print('YES' if -(-N//2)>=K else 'NO')
    
resolve()