Determine if we can choose K different integers between 1 and N (inclusive) so that no two of them differ by 1.
import math
N, K = map(int, input().split())
ans = 'Yes'
if math.ceil(N / 2) < K:
  ans = 'No'
print(ans)
n,k=map(int,input().split());print('YNEOS'[k*2>=n+2::2])