#%%
n, k = map(int, input().split())
if n - 1 >= 2*(k-1):
    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 - 1 >= 2*(k-1):
    print('YES')
else:
    print('NO') n - 1 >= 2*(k-1) n - 1 n 1 2*(k-1) 2 k-1 k 1 print('YES') print 'YES' print('NO') print 'NO' k = map(int, input().split()) map(int, input().split()) k n, k = map(int, input().split()) map(int, input().split()) n
#%%
n, k = map(int, input().split())
if n - 1 >= 2*(k-1):
    print('YES')
else:
    print('NO')