dxy = ((-2,-1),(-2,1),(-1,-2),(-1,2),(1,-2),(1,2),(2,-1),(2,1))
goal = tuple(map(int,raw_input().split(" ")))
q = [((0,0),3)]
visit = set([(0,0)])
while len(q) > 0:
	hp,hs = q.pop(0)
	if hp == goal:
		print "YES"
		break
	for dx,dy in dxy:
		nxt = (hp[0]+dx, hp[1]+dy)
		if nxt not in visit and hs > 0:
			visit.add(nxt)
			q.append((nxt,hs-1))
else:
	print "NO"