How to determine Router ID on Cisco Routers that running OSPF routing

Have threes factors to determine Router ID in OSPF router
1. You can configure manually the Router ID by following command in Router Mode:
router-id A.B.C.D
example: router-id 1.1.1.1
2. If you do not configure manually the Router ID. OSPF Router will determine the Router ID by chosen the heighest IP Address of logical interfaces (loopback interfaces).
3. If haven't any logical interfaces. OSPF Router will chose the heighest IP address of any physical interfaces