1=>((a|b|\p{Nd}){1,2}|aaa|bbbb){1,2} 2bab 3aaca 4aaabbbb 5a0b 6aa0aaa 7b0aaa 8=>(\d{1,3}\.){3}\d{1,3} 91.2.3.4 101.22.333.44 111.2.3 121..2.3 13