def resolve():
    N,K = map(int,input().split())
    if N%2 ==0:
        print("YES" if N//2 >= K else "NO")
    else:
        print("YES" if (N+1)//2 >=K else "NO")

    
resolve() def resolve():
    N,K = map(int,input().split())
    if N%2 ==0:
        print("YES" if N//2 >= K else "NO")
    else:
        print("YES" if (N+1)//2 >=K else "NO")

     resolve N,K = map(int,input().split()) N map(int,input().split()) map int input().split() ().split () input split K if N%2 ==0:
        print("YES" if N//2 >= K else "NO")
    else:
        print("YES" if (N+1)//2 >=K else "NO")

     N%2 ==0 N%2 N 2 0 print("YES" if N//2 >= K else "NO") print "YES" if N//2 >= K else "NO" N//2 >= K N//2 N 2 K "YES" "NO" print("YES" if (N+1)//2 >=K else "NO") print "YES" if (N+1)//2 >=K else "NO" (N+1)//2 >=K (N+1)//2 N+1 N 1 2 K "YES" "NO" resolve() resolve def resolve():
    N,K = map(int,input().split())
    if N%2 ==0:
        print("YES" if N//2 >= K else "NO")
    else:
        print("YES" if (N+1)//2 >=K else "NO")

     def resolve():
    N,K = map(int,input().split())
    if N%2 ==0:
        print("YES" if N//2 >= K else "NO")
    else:
        print("YES" if (N+1)//2 >=K else "NO")

     resolve
def resolve():
    N,K = map(int,input().split())
    if N%2 ==0:
        print("YES" if N//2 >= K else "NO")
    else:
        print("YES" if (N+1)//2 >=K else "NO")

    
resolve()