handouts/ho03.tex
changeset 967 ce5de01b9632
parent 936 0b5f06539a84
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966:4189cb63e5db 967:ce5de01b9632
   812   case STAR(r1) => NFA_STAR(thompson(r1))
   812   case STAR(r1) => NFA_STAR(thompson(r1))
   813 }
   813 }
   814 \end{lstlisting}}
   814 \end{lstlisting}}
   815 
   815 
   816 \noindent
   816 \noindent
   817 It calculates a NFA from a regular expressions. At last we can run
   817 It calculates a NFA from a regular expression. At last we can run
   818 NFAs for the our evil regular expression examples.  The graph on the
   818 NFAs for our evil regular expression examples.  The graph on the
   819 left shows that when translating a regular expression such as
   819 left shows that when translating a regular expression such as
   820 $a^{?\{n\}} \cdot a^{\{n\}}$ into a NFA, the size can blow up and then
   820 $a^{?\{n\}} \cdot a^{\{n\}}$ into a NFA, the size can blow up and then
   821 even the relative fast (on small examples) breadth-first search can be
   821 even the relative fast (on small examples) breadth-first search can be
   822 slow\ldots the red line maxes out at about 15 $n$s.
   822 slow\ldots the red line maxes out at about 15 $n$s.
   823 
   823