Answer： foo Point(3)
Answer: k$ Point(2)
Answer: fu\b Point(4) 或者 u\b
Answer:[a-f][a-f][a-f][a-f] Point(20)
Answer: (...).*\1 Point(9)
Answer: ^(?!.*(.)(.)\2\1) Point(17)
Answer: ^(.)(.).*\2\1$
持续更新...
My Answer in Regex Golf
原文：http://www.cnblogs.com/xiyin/p/7986230.html
