git mv *.hint -> README.md
There is one exception:
$ find . -name '*.hint' -execdir git mv '{}' README.md \;
git statufatal: destination exists, source=1992/albert/albert.hint, destination=1992/albert/README.md
Looking at the two files they differ quite a bit so I've not changed it.
I'll bring this up on GitHub.
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Most Educational:
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Adrian Mariano
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University of Washington
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2729 72nd Ave SE
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Mercer Island, WA 98040
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USA
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Judges' comments:
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To build:
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make adrian
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Try:
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adrian adrian.grep.try < adrian.hint
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For the slow minded, try:
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adsleep 32767
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Once you get past the obfuscation, you have an opportunity to learn
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about regular expressions and state machines.
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NOTE: Some compilers have had trouble optimizing this entry.
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Selected notes from the author:
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ADrian's GREP (adgrep)
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For those confused by the complexity of full-blown egrep style regular
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expressions, this program offers an alternative. It implements an
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equivalent search, using a deterministic finite automaton.
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A deterministic finite automaton consists of a finite set of states,
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along with transition rules to move from one state to another, an initial
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state, and a set of accepting states. The automaton takes a string as
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input and begins in the start state. It reads a character of the string
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and consults the rules for the current state, moving to the new state
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indicated by the appropriate rule. This process is repeated until the
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string is consumed. If the current state at this point is one of the
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accepting states, then the string is accepted.
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The deterministic finite automaton is specified as a series of rules for
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each state:
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<state> chars1 <dest1> chars2 <dest2> ...
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chars1 is a list of characters (only the first 8 are significant) which
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should trigger a transition to <dest1>. <dest1> is another state which
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should have a similar specification somewhere. A state is accepting if
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it is specified in square brackets: [final], and state strings are
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significant to only eight characters.
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Example 1: matches ^abc$
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<q0> a <q1> The first state to appear is the start state
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<q1> b <q2>
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<q2> c [q3]
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[q3]
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Technically, a deterministic finite automaton should have a rule for each
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possible input character at each state. To simplify descriptions of the
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automata, if no rule is present, the string will not be accepted. Also,
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the '.' character matches any character if it occurs first in the
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character list.
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Example 2: ^abc
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<q0> a <q1>
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<q1> b <q2>
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<q2> c [q3]
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[q3] . [q3]
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Example 3: abc$
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<q0> a <q1> . <q0>
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<q1> b <q2> a <q1> . <q0>
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<q2> c [q3] a <q1> . <q0>
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[q3] . <q1>
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Example 4: ^(abc)*$
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[q0] a <q1>
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<q1> b <q2>
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<q2> c [q0]
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Example 5: ^[ab][cd][ef]$
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<q0> ab <q1>
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<q1> cd <q2>
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<q2> ef [q3]
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[q3]
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Example 6: ^(abc|efg)$
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<q0> a <q1> e <q3>
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<q1> b <q2>
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<q2> c [q5]
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<q3> f <q4>
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<q4> g [q5]
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[q5]
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With the automaton specification in 'filename', invoke the program by
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typing
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adgrep 'filename'
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It will read stdin and print out all the lines which the automaton
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accepts. If the file cannot be opened, a system error message will
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be printed. If the input contains errors, then an error message along
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with the number of the offending line will be printed to stderr. The
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number of rules for each state is limited to 17. If more than 17 rules
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are present, you get the error to_many_rules, and the state that was
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being processed is printed. Error no_destination occurs if you specify a
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set of characters, but no destination state, and error too_many_states
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occurs if your automaton has more than 257 states.
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Running
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adgrep from < your_mailbox
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will perform a function similar to that of the unix from command.
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If no filename is specified on the command line, then "adgrep.c" is used
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as the specification for the automaton. (This file has been renamed
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to adrian.c by the judges.) In this case, the program will search for
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matches to the regular expression:
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^.[^|C][^w[Q]*(Q|[w[]c).*|^.[C|]$
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I suggest using adgrep.c as input, and storing the output in adwc.c:
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adgrep < adgrep.c > adwc.c
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Compiling the new file, mywc.c, yields a clone of the unix wc command. It
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runs on one file (defaulting to "adgrep.c" if no file is given) and
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displays the number of lines, words, and bytes in the input file.
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Another possibly interesting automaton can be created by slightly
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adjusting the adgrep.c file. Change the first line to read
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/* . echo| . */
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and repeat the process above
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adgrep <adgrep.c > adecho.c
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The new file now contains all lines which match
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^.[^5|m^]*[m^]([e=p,;]|[^e=+p,;].*)$
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Compile and run. This is an echo clone. Note the efficient algorithm
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employed.
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Two other adjustments to the first line also yield useful results. By
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changing it to
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/* . head; . */
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you can search for matches to
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^.[^W]*W..*$
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By some freak happenstance, lines of adgrep.c which match this regular
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expression form a unix head command. It prints the first ten lines of
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the file specified on the command line (or adgrep.c if no file is
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specified).
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By setting the first line to
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/* . basename . */
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a clone of the unix basename command can be unearthed. The automaton will
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search for
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^.[^j]*jr.*$
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on standard input. And the program which results by running adgrep.c
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through this filter requires two parameters. The first is meant to be a
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filename, and the second, an extension. All leading pathname components
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are removed from the filename, and the extension is removed if present.
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The resulting base name is printed to stdout.
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Lastly, by setting the first line to
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/* . sleep . */
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you can search for
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^.[^(~][^s]*sl.*$
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Filtering adgrep.c through this search yields a clone of the sleep
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command. Invoke with a single integer parameter, and it will pause
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for that many seconds.
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If either adbasename or adsleep is invoked with too few parameters,
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the program will print the error message:
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Segmentation fault (core dumped)
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(The exact text of the above error messages varies from machine to
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machine.) The four programs which read from stdin require lines
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shorter than 999 characters.
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The other info files are adrian.grep.[1-6] which contain the six
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examples that appear above, and from, which is used to emulate the
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unix from command. For reasons of clarity, the name "from" should
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probably not be changed if possible. I wouldn't want to be accused of
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confusing people by giving the input files weird names.
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If you want to change the default input filename (line 80) you must be
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careful to choose a name that doesn't match the wrong search patterns,
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introducing extra lines into one of the programs.
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The program will produce at least one warning and possible several
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when compiled depending on the compiler.
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Copyright (c) 1992, Landon Curt Noll & Larry Bassel.
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All Rights Reserved. Permission for personal, educational or non-profit use is
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granted provided this this copyright and notice are included in its entirety
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and remains unaltered. All other uses must receive prior permission in writing
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from both Landon Curt Noll and Larry Bassel.
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