1*7c568831SAndroid Build Coastguard Worker=>((a|b|\p{Nd}){1,2}|aaa|bbbb){1,2} 2*7c568831SAndroid Build Coastguard Workerbab 3*7c568831SAndroid Build Coastguard Workeraaca 4*7c568831SAndroid Build Coastguard Workeraaabbbb 5*7c568831SAndroid Build Coastguard Workera0b 6*7c568831SAndroid Build Coastguard Workeraa0aaa 7*7c568831SAndroid Build Coastguard Workerb0aaa 8*7c568831SAndroid Build Coastguard Worker=>(\d{1,3}\.){3}\d{1,3} 9*7c568831SAndroid Build Coastguard Worker1.2.3.4 10*7c568831SAndroid Build Coastguard Worker1.22.333.44 11*7c568831SAndroid Build Coastguard Worker1.2.3 12*7c568831SAndroid Build Coastguard Worker1..2.3 13