wherein {HEAD ~ a nearest distance} between the first dummy metal and the second dummy metal is more than {TAIL ~ a nearest distance} between the third dummy metal and the fourth dummy metal, and 
wherein { HEAD ~ a nearest distance } between the first dummy metal and the second dummy metal is more than { TAIL ~ a nearest distance } between the third dummy metal and the fourth dummy metal , and
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH