#coding:utf-8

def func():

	old=map(int,raw_input().split('.'))
	hantei=map(int,raw_input().split('.'))

	if hantei[0] < old[0]:
		return 'YES'
	
	if hantei[0] == old[0]:
		if hantei[1] < old[1]:
			return 'YES'
		elif hantei[1] == old[1]:
			if hantei[2] <= old[2]:
				return 'YES'
			else:
				return 'NO'
		else:
			return 'NO'
		
	if old[0] < hantei[0]:
		return 'NO'
		
if __name__=='__main__':
	print func()