N,K=map(int,input().split())

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

if N%2==0:
  if K<=N//2:
    print("YES")
  else:
    print("NO")
else:
  if K<=(N+1)//2:
    print("YES")
  else:
    print("NO")