function score(classes,		sum,key,i,c) {
	for (key in classes) {
		sum += classes[key]^2
	}
	return sqrt(sum)
}

BEGIN {
	g["e"] = 12
	g["d"] = 8
	g["m"] = 2
	p["e"] = "<"
	p["d"] = "<"
	p["m"] = "<"
	for (key in g)
		ignorep[g[key]] = 1
	if (!(7 in ignorep))
		print "yes"
}