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28 lines
1.1 KiB
Text
28 lines
1.1 KiB
Text
While teaching a data structures course at University of California,
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Irvine, I developed a program called GPERF that generates perfect hash
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functions for sets of key words. A perfect hash function is simply:
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A hash function and a data structure that allows
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recognition of a key word in a set of words using
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exactly 1 probe into the data structure.
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The gperf.texinfo file explains how the program works, the form of the
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input, what options are available, and hints on choosing the best
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options for particular key word sets. The texinfo file is readable
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both via the GNU emacs `info' command, and is also suitable for
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typesetting with TeX. The texinfo.tex macros needed to run
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gperf.texinfo through TeX are available in the GNU GCC release. If
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you don't have access to these please email me and I'll send them to
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you (about 75k).
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The enclosed Makefile creates the executable program ``gperf'' and
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also runs some tests.
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Output from the GPERF program is used to recognize reserved words in
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the GNU C, GNU C++, and GNU Pascal compilers, as well as with the GNU
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indent program.
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Happy hacking!
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Douglas C. Schmidt
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schmidt@ics.uci.edu
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