Jianguo Lu : regular expression and automata

Jianguo Lu 2 Try RegexTester Running at course web site as an applet; – Write regular expressions and try the match(), find() methods; Try the string 3314 instead of 3.14

Jianguo Lu 3 Try FSM simulator Run the simulator –The java code can be downloaded at –Unzip the zip file >unzip fsm.zip –Go to the directory fsmsim_bgm/classes –Run the java program: >java FSM Define the FSM in the text file; –The text files are in fsm-sources Generate the transition diagram; –Machine/new machine Run the simulator and observe how strings are recognized.

Jianguo Lu 4 select “save target as”

Jianguo Lu 5 Construct and run a dfa from a text file

Jianguo Lu 6 NFA //Type (a|b)*abb Fig in dragon book a b // input alphabet q0 q1 q2 q3 // Machine states q0// the initial state q3 // final state q0 b q0 // transitions: input state, input symbol, output state q3 b q0 q1 a q1 q2 a q1 q3 a q1 q0 a q1 q1 b q2 q2 b q3 end

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10 Construct a dfa in GUI

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Jianguo Lu 12 JFLAP: RE  NFA  DFA  m. DFA

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