a,b = map(int, input().split(" "))
b = b -1
if b==0:
  print("YES")
elif (a-1)//b >=2:
  print("YES")
else:
  print("NO") a,b = map(int, input().split(" ")) a map(int, input().split(" ")) map int input().split(" ") ().split () input split " " b b = b -1 b b -1 b 1 if b==0:
  print("YES")
elif (a-1)//b >=2:
  print("YES")
else:
  print("NO") b==0 b 0 print("YES") print "YES" elif (a-1)//b >=2:
  print("YES") (a-1)//b >=2 (a-1)//b a-1 a 1 b 2 print("YES") print "YES" print("NO") print "NO" b = map(int, input().split(" ")) map(int, input().split(" ")) b b = b -1 b -1 b a,b = map(int, input().split(" ")) map(int, input().split(" ")) a
a,b = map(int, input().split(" "))
b = b -1
if b==0:
  print("YES")
elif (a-1)//b >=2:
  print("YES")
else:
  print("NO")
