import sys
n,k = input().split()

N = int(n)
K = int(k)

if N < K:
    print("NO")
    #sys.exit()
    
elif N == 1 and K == 1:
    print("YES")
    #sys.exit()

elif N % 2 == 0:
    if 2 * K <= N:
        print("YES")
    else:
        print("NO")

elif N % 2 == 1:
    if 2 * K <= N+1:
        print("YES")
    else:
        print("NO") import sys sys n,k = input().split() n input().split() ().split () input split k N = int(n) N int(n) int n K = int(k) K int(k) int k if N < K:
    print("NO")
    #sys.exit()
    
elif N == 1 and K == 1:
    print("YES")
    #sys.exit()

elif N % 2 == 0:
    if 2 * K <= N:
        print("YES")
    else:
        print("NO")

elif N % 2 == 1:
    if 2 * K <= N+1:
        print("YES")
    else:
        print("NO") N < K N K print("NO") print "NO" elif N == 1 and K == 1:
    print("YES")
    #sys.exit() N == 1 and K == 1 N == 1 N 1 K == 1 K 1 print("YES") print "YES" elif N % 2 == 0:
    if 2 * K <= N:
        print("YES")
    else:
        print("NO") N % 2 == 0 N % 2 N 2 0 if 2 * K <= N:
        print("YES")
    else:
        print("NO") 2 * K <= N 2 * K 2 K N print("YES") print "YES" print("NO") print "NO" elif N % 2 == 1:
    if 2 * K <= N+1:
        print("YES")
    else:
        print("NO") N % 2 == 1 N % 2 N 2 1 if 2 * K <= N+1:
        print("YES")
    else:
        print("NO") 2 * K <= N+1 2 * K 2 K N+1 N 1 print("YES") print "YES" print("NO") print "NO" N = int(n) int(n) N K = int(k) int(k) K n,k = input().split() input().split() n k = input().split() input().split() k
import sys
n,k = input().split()

N = int(n)
K = int(k)

if N < K:
    print("NO")
    #sys.exit()
    
elif N == 1 and K == 1:
    print("YES")
    #sys.exit()

elif N % 2 == 0:
    if 2 * K <= N:
        print("YES")
    else:
        print("NO")

elif N % 2 == 1:
    if 2 * K <= N+1:
        print("YES")
    else:
        print("NO")