做了一遍，然后搜集了目前的最优答案：
- Warmup (207):
foo - Anchors (208):
k$ - Ranges (202):
^[a-f]+$ - Backrefs (201):
(...).*\1 - Abba (195):
^(?!.*(.)\1)|ef - A man, a plan (177):
^(.)[^p].*\1$ - Prime (286):
^(?!(xx+)\1+$) - Four (199):
(.)(.\1){3} - Order (199):
^.{5}[^e]?$ - Triples (596):
00($|3|6|9|12|15)|4.2|.1.+4|55|.17 - Glob (397):
[bncrw][bporn]|^p|c$|ta - Balance (447):
^(<(<(<(<(<(...)*>)*>)*>)*>)*>)*$ - Powers (93):
^(?!(x(xx)+)\1*$) - Long count (256):
((.+)0\2+1){8} - Alphabetical (317):
.r.{32}r|a.{10}te|n.n.. - Powers 2 (88):
^(.|(...)+)$
这东西真是有趣呀 ^ ^