A.172.16.42.0 B.172.16.107.0 C.172.16.208.0 D.172.16.252.0 E.172.16.254.0
A.255.255.255.0 B.255.255.255.128 C.255.255.252.0 D.255.255.255.224 E.255.255.255.192 F.255.255.248.0
A.128 B.192 C.254 D.256 E.510