1*7c568831SAndroid Build Coastguard Worker=>(a{1,2}|ab){2}
2*7c568831SAndroid Build Coastguard Workerabab
3*7c568831SAndroid Build Coastguard Worker=>((1?[0-9]{1,2}|2[0-4][0-9]|25[0-5])\.){3}(1?[0-9]{1,2}|2[0-4][0-9]|25[0-5])
4*7c568831SAndroid Build Coastguard Worker192.168.254.0
5