Path: csiph.com!eternal-september.org!feeder.eternal-september.org!news.iecc.com!.POSTED.news.iecc.com!nerds-end
From: Andy <borucki.andrzej@gmail.com>
Newsgroups: comp.compilers
Subject: Reachability of DFA part
Date: Fri, 20 Dec 2019 04:53:26 -0800 (PST)
Organization: Compilers Central
Lines: 5
Sender: news@iecc.com
Approved: comp.compilers@iecc.com
Message-ID: <19-12-008@comp.compilers>
Mime-Version: 1.0
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 8bit
Injection-Info: gal.iecc.com; posting-host="news.iecc.com:2001:470:1f07:1126:0:676f:7373:6970"; logging-data="51676"; mail-complaints-to="abuse@iecc.com"
Keywords: DFA, question
Posted-Date: 20 Dec 2019 10:54:11 EST
X-submission-address: compilers@iecc.com
X-moderator-address: compilers-request@iecc.com
X-FAQ-and-archives: http://compilers.iecc.com
Xref: csiph.com comp.compilers:2389

Sometmimes part of DFA can be unreached: ab(a|b)*ba - ba is unreachable.
Solution is check back transitions - must be >0 back transitions from each
state (and >0 transitions from each non-finished state)? Or are better methods
- if can exists cases, if all backtransitions count > 0 and still
unreachable?