Cody Boone Ferguson
9fdeaf1098
The manifest was updated for 1994/tvr. Rebuilt .entry.json and index.html. Bug status changed in 1994/tvr as well. The judges noted that it has an incorrect result in some cases but the author actually noted this as a feature so it should not be fixed. Other fixes/updates were made in the bugs file as well. A number of other entries of 1994 had minor fixes (formatting, links and similar things).
114 lines
2.9 KiB
Markdown
114 lines
2.9 KiB
Markdown
## To build:
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``` <!---sh-->
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make all
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```
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There is an alternate build (same code, alternate build) that uses more memory.
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See [Alternate code](#alternate-code) below for more details.
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## To use:
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``` <!---sh-->
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./weisberg
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```
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## Try:
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``` <!---sh-->
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./try.sh
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```
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If you have `primes(1)` installed you might also wish to try:
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``` <!---sh-->
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./primes.sh number
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```
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where `number` is a positive number, defaulting to 15. The
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[try.sh](%%REPO_URL%%/1994/weisberg/try.sh) script will also `try` :-) and do
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this.
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## Alternate code:
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If you liked what you saw from the above program, and happen to
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have some 512 megabytes of virtual memory lying around with to do
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something with you might try this build.
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### Alternate build:
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``` <!---sh-->
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make alt
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```
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### Alternate use:
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``` <!---sh-->
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./weisberg.alt
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```
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Lesser systems will find this alternative version a good way to create
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a core file. :-)
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## Judges' remarks:
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This entry confuses some C-preprocessors and some C-beautifiers.
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We found one cpp that processed this source differently when
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it was read on `stdin` instead of via `cc -E`.
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## Author's remarks:
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### Description
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The following short program implements the "Yet Another" algorithm for
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generating prime numbers. It will generate all primes up to 33554432,
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displaying them to the standard output as it churns along. As 33554432
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is rather large on most machines, this code may take quite some time to
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run to completion, so as an added feature, it will cease execution upon
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reception of a signal (any will do equally well), as well as in the
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event of a system shutdown or reboot.
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### Bugs
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The alternative build ([weisberg.c](%%REPO_URL%%/1994/weisberg/weisberg.c)
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compiled to `weisberg.alt`) has never actually run
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to completion. After running for close to a week it had reached somewhere around
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250e6, when it became necessary to test the reboot feature (which worked
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remarkably well). As there are quite a lot of primes to be found before reaching
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`INT_MAX`, the output produced can be quite overwhelming so it's recommended to pipe
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the output through your favorite pager (`more` or `less`), and not output to a
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paper output device (unless you have *LOTS* of paper).
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### Technical
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The original "Yet Another Prime Program" algorithm used here was developed as a
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Computer Architecture course micro-programming exercise, and was designed to
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take full advantage of the UR300 micro-architecture to achieve blindingly fast
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speed. It was ported to C specifically for the IOCCC. In the
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conversion/obfuscation step some of (much of) the blazing speed was lost, but as
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a bonus, the understandability of the code was reduced to zero.
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<!--
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Copyright © 1984-2024 by Landon Curt Noll. All Rights Reserved.
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You are free to share and adapt this file under the terms of this license:
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Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
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For more information, see:
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https://creativecommons.org/licenses/by-sa/4.0/
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-->
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