from sys import stdin
n,m = map(int,stdin.readline().split())
if (n+1)/2 >=m:
 print 'YES'
else:
 print 'NO' from sys import stdin n,m = map(int,stdin.readline().split()) n map(int,stdin.readline().split()) map int stdin.readline().split() stdin.readline().split stdin.readline() stdin.readline stdin readline split m if (n+1)/2 >=m:
 print 'YES'
else:
 print 'NO' (n+1)/2 >=m (n+1)/2 n+1 n 1 2 m print print m = map(int,stdin.readline().split()) map(int,stdin.readline().split()) m n,m = map(int,stdin.readline().split()) map(int,stdin.readline().split()) n
from sys import stdin
n,m = map(int,stdin.readline().split())
if (n+1)/2 >=m:
 print 'YES'
else:
 print 'NO'