This directory contains some examples illustrating techniques for extractinghigh-performance from flex scanners.  Each program implements a simplifiedversion of the Unix "wc" tool: read text from stdin and print the number ofcharacters, words, and lines present in the text.  All programs were compiledusing gcc (version unavailable, sorry) with the -O flag, and run on aSPARCstation 1+.  The input used was a PostScript file, mainly containingfigures, with the following "wc" counts:	lines  words  characters	214217 635954 2592172The basic principles illustrated by these programs are:	- match as much text with each rule as possible	- adding rules does not slow you down!	- avoid backing upand the big caveat that comes with them is:	- you buy performance with decreased maintainability; make	  sure you really need it before applying the above techniques.See the "Performance Considerations" section of flexdoc for moredetails regarding these principles.The different versions of "wc":	mywc.c		a simple but fairly efficient C version	wc1.l	a naive flex "wc" implementation	wc2.l	somewhat faster; adds rules to match multiple tokens at once	wc3.l	faster still; adds more rules to match longer runs of tokens	wc4.l	fastest; still more rules added; hard to do much better		using flex (or, I suspect, hand-coding)	wc5.l	identical to wc3.l except one rule has been slightly		shortened, introducing backing-upTiming results (all times in user CPU seconds):	program	  time 	 notes	-------   ----   -----	wc1       16.4   default flex table compression (= -Cem)	wc1        6.7   -Cf compression option	/bin/wc	   5.8	 Sun's standard "wc" tool	mywc	   4.6   simple but better C implementation!	wc2	   4.6   as good as C implementation; built using -Cf	wc3	   3.8   -Cf	wc4	   3.3   -Cf	wc5	   5.7   -Cf; ouch, backing up is expensive