RouterA(config)# router ospf 1
RouterA(config-router)# network 172.16.4.0 0.0.1.255 area 1
RouterA(config)# router ospf 10*
RouterA(config-router)# network 172.16.4.0 0.0.0.255 area 0
RouterA(config-router)# network 172.16.5.0 0.0.0.255 area 0
RouterA(config)# router ospf 10
RouterA(config-router)# area 0 network 172.16.4.0 0.0.1.255
RouterA(config)# router ospf 0
RouterA(config-route)# network 172.16.4.0 0.0.255.255 area 0
RouterA(config)# router ospf 0
RouterA(config-router)# network 172.16.4.0 255.255.255.0
RouterA(config-router)# network 172.16.5.0 255.255.255.0
RouterA(config)# router ospf 1
RouterA(config-router)# network 172.16.4.0 255.255.254.0 area 0