mirror/ioccc
1
0 Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
Files
master
ioccc/2012/tromp/how.html
T
Landon Curt Noll f29b37e49a improve HTML menus, add social.html, prep for IOCCC28 winners 
Prepare for the winners of **IOCCC28**.

> However these are not the 2024 droids you are looking for.  :-)

The HTML menu (both JavaScript and non-JavaScript) has been updated.

The `Status -> Rules and guidelines' have been replaced with two
separate menus `Status -> IOCCC rules` and `Status -> IOCCC guidelines`.

Added a new top level `social.html` page: built from a new `social.md`.

Sorted rules for building specific web pages in the top level `Makefile`.
Added `make social` to make the `social.html` page from `social.md`.

The `bin/gen-top-html.sh` now is able to process a argument of **social**
to process the new top level `social.html` page.

Changed `bin/gen-top-html.sh` VERSION from "2.0.0 2025-03-13"
to "2.0.1 2025-07-25".

Below `About -> Home page` a new `About -> IOCCC social media` menu item
as added.

Because the menu change touched every HTML file, we changed the general
copyright date range for HTML files from "1984-2024" to "1984-2025"
due to the extensive changes made for **IOCCC28**.

Those markdown files that were modified in 2025 had their copyright date
range also changed from "1984-2024" to "1984-2025".

Rebuilt tarballs and sitemap due to the extensive HTML rebuilding.

Ran `make update` to perform the above.
2025-07-26 13:06:29 -07:00

597 lines
19 KiB
HTML
Raw Permalink Blame History

This file contains ambiguous Unicode characters
This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<!-- START: two lines up starts content from: inc/top.default.html -->
<!-- END: this line ends content from: inc/top.default.html -->
<!-- START: this line starts content from: inc/head.default.html -->
<head>
<link rel="stylesheet" href="../../ioccc.css">
<link href="https://fonts.googleapis.com/css2?family=Outfit:wght@100..900&display=swap" rel="stylesheet">
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=yes">
<title>The International Obfuscated C Code Contest</title>
<link rel="icon" type="image/x-icon" href="../../favicon.ico">
<meta name="description" content="how.md for 2012/tromp">
<meta name="keywords" content="IOCCC, 2012/tromp, how.md">
</head>
<!-- !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! -->
<!-- !!! DO NOT MODIFY THIS FILE - This file is generated by a tool !!! -->
<!-- !!! DO NOT MODIFY THIS FILE - This file is generated by a tool !!! -->
<!-- !!! DO NOT MODIFY THIS FILE - This file is generated by a tool !!! -->
<!-- !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! -->
<!-- END: this line ends content from: inc/head.default.html -->
<!-- -->
<!-- This web page was formed via the tool: bin/gen-other-html.sh -->
<!-- The content of main section of this web page came from: 2012/tromp/how.md -->
<!-- -->
<!-- !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! -->
<!-- !!! Do not modify this web page, instead modify the file: 2012/tromp/how.md !!! -->
<!-- !!! Do not modify this web page, instead modify the file: 2012/tromp/how.md !!! -->
<!-- !!! Do not modify this web page, instead modify the file: 2012/tromp/how.md !!! -->
<!-- !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! -->
<!-- Markdown content was converted into HTML via the tool: bin/md2html.sh -->
<!-- START: this line starts content from: inc/body.default.html -->
<body>
<!-- END: this line ends content from: inc/body.default.html -->
<!-- START: this line starts content from: inc/topbar.default.html -->
<div class="theader">
<nav class="topbar">
<div class="container">
<div class="logo">
<a href="../../index.html" class="logo-link">
IOCCC
</a>
</div>
<div class="topbar-items">
<div class="item">
<span class="item-header">
Entries
</span>
<div class="sub-item">
<div class="outfit-font">
<a href="../../years.html" class="sub-item-link">
Winning entries
</a>
</div>
<div class="outfit-font">
<a href="../../authors.html" class="sub-item-link">
Winning authors
</a>
</div>
<div class="outfit-font">
<a href="../../location.html" class="sub-item-link">
Location of authors
</a>
</div>
<div class="outfit-font">
<a href="../../bugs.html" class="sub-item-link">
Bugs and (mis)features
</a>
</div>
<div class="outfit-font">
<a href="../../faq.html#fix_an_entry" class="sub-item-link">
Fixing entries
</a>
</div>
<div class="outfit-font">
<a href="../../faq.html#fix_author" class="sub-item-link">
Updating author info
</a>
</div>
</div>
</div>
<div class="item">
<span class="item-header">
Status
</span>
<div class="sub-item">
<div class="outfit-font">
<a href="../../news.html" class="sub-item-link">
News
</a>
</div>
<div class="outfit-font">
<a href="../../status.html" class="sub-item-link">
Contest status
</a>
</div>
<div class="outfit-font">
<a href="../../next/rules.html" class="sub-item-link">
IOCCC rules
</a>
</div>
<div class="outfit-font">
<a href="../../next/guidelines.html" class="sub-item-link">
IOCCC guidelines
</a>
</div>
<div class="outfit-font">
<a href="../../markdown.html" class="sub-item-link">
Markdown guidelines
</a>
</div>
<div class="outfit-font">
<a href="../../SECURITY.html" class="sub-item-link">
Security policy
</a>
</div>
</div>
</div>
<div class="item">
<span class="item-header">
FAQ
</span>
<div class="sub-item">
<div class="outfit-font">
<a href="../../faq.html" class="sub-item-link">
Frequently asked questions
</a>
</div>
<div class="outfit-font">
<a href="../../quick-start.html#enter" class="sub-item-link">
Enter the IOCCC
</a>
</div>
<div class="outfit-font">
<a href="../../faq.html#compiling" class="sub-item-link">
Compiling entries
</a>
</div>
<div class="outfit-font">
<a href="../../faq.html#running_entries" class="sub-item-link">
Running entries
</a>
</div>
<div class="outfit-font">
<a href="../../faq.html#help" class="sub-item-link">
How to help
</a>
</div>
</div>
</div>
<div class="item">
<span class="item-header">
About
</span>
<div class="sub-item">
<div class="outfit-font">
<a href="../../index.html" class="sub-item-link">
Home page
</a>
</div>
<div class="outfit-font">
<a href="../../social.html" class="sub-item-link">
IOCCC social media
</a>
</div>
<div class="outfit-font">
<a href="../../about.html" class="sub-item-link">
About the IOCCC
</a>
</div>
<div class="outfit-font">
<a href="../../judges.html" class="sub-item-link">
The judges
</a>
</div>
<div class="outfit-font">
<a href="../../thanks-for-help.html" class="sub-item-link">
Thanks for the help
</a>
</div>
<div class="outfit-font">
<a href="../../contact.html" class="sub-item-link">
Contact us
</a>
</div>
</div>
</div>
</div>
</div>
</nav>
<div class="header-mobile-menu">
<noscript>
<a href="../../nojs-menu.html" class="topbar-js-label">
Please Enable JavaScript
</a>
</noscript>
<button id="header-open-menu-button" class="topbar-mobile-menu">
<img
src="../../png/hamburger-icon-open.png"
alt="hamburger style menu icon - open state"
width=48
height=48>
</button>
<button id="header-close-menu-button" class="hide-content">
<img
src="../../png/hamburger-icon-closed.png"
alt="hamburger style menu icon - closed state"
width=48
height=48>
</button>
<div id="mobile-menu-panel" class="hide-content">
<div class="mobile-menu-container">
<div class="mobile-menu-wrapper">
<div class="mobile-menu-item">
Entries
</div>
<div class="mobile-submenu-wrapper">
<a class="mobile-submenu-item" href="../../years.html">
Winning entries
</a>
<a class="mobile-submenu-item" href="../../authors.html">
Winning authors
</a>
<a class="mobile-submenu-item" href="../../location.html">
Location of authors
</a>
<a class="mobile-submenu-item" href="../../bugs.html">
Bugs and (mis)features
</a>
<a class="mobile-submenu-item" href="../../faq.html#fix_an_entry">
Fixing entries
</a>
<a class="mobile-submenu-item" href="../../faq.html#fix_author">
Updating author info
</a>
<a class="mobile-submenu-item" href="../../thanks-for-help.html">
Thanks for the help
</a>
</div>
</div>
<div class="mobile-menu-wrapper">
<div class="mobile-menu-item">
Status
</div>
<div class="mobile-submenu-wrapper">
<a class="mobile-submenu-item" href="../../news.html">
News
</a>
<a class="mobile-submenu-item" href="../../status.html">
Contest status
</a>
<a class="mobile-submenu-item" href="../../next/rules.html">
IOCCC rules
</a>
<a class="mobile-submenu-item" href="../../next/guidelines.html">
IOCCC guidelines
</a>
<a class="mobile-submenu-item" href="../../markdown.html">
Markdown guidelines
</a>
<a class="mobile-submenu-item" href="../../SECURITY.html">
Security policy
</a>
</div>
</div>
<div class="mobile-menu-wrapper">
<div class="mobile-menu-item">
FAQ
</div>
<div class="mobile-submenu-wrapper">
<a class="mobile-submenu-item" href="../../faq.html">
Frequently asked questions
</a>
<a class="mobile-submenu-item" href="../../quick-start.html#enter">
Enter the IOCCC
</a>
<a class="mobile-submenu-item" href="../../faq.html#compiling">
Compiling entries
</a>
<a class="mobile-submenu-item" href="../../faq.html#running_entries">
Running entries
</a>
<a class="mobile-submenu-item" href="../../faq.html#help">
How to help
</a>
</div>
</div>
<div class="mobile-menu-wrapper">
<div class="mobile-menu-item">
About
</div>
<div class="mobile-submenu-wrapper">
<a class="mobile-submenu-item" href="../../index.html">
Home page
</a>
<a class="mobile-submenu-item" href="../../social.html">
IOCCC social media
</a>
<a class="mobile-submenu-item" href="../../about.html">
About the IOCCC
</a>
<a class="mobile-submenu-item" href="../../judges.html">
The judges
</a>
<a class="mobile-submenu-item" href="../../contact.html">
Contact us
</a>
</div>
</div>
</div>
</div>
</div>
</div>
<script>
var headerOpenMenuButton = document.getElementById("header-open-menu-button");
var headerCloseMenuButton = document.getElementById("header-close-menu-button");
var mobileMenuPanel = document.getElementById("mobile-menu-panel");
headerOpenMenuButton.addEventListener("click", () => {
headerOpenMenuButton.classList.remove("topbar-mobile-menu");
headerOpenMenuButton.classList.add("hide-content");
headerCloseMenuButton.classList.remove("hide-content");
headerCloseMenuButton.classList.add("topbar-mobile-menu");
mobileMenuPanel.classList.remove("hide-content");
mobileMenuPanel.classList.add("topbar-mobile-panel");
});
headerCloseMenuButton.addEventListener("click", () => {
headerCloseMenuButton.classList.remove("topbar-mobile-menu");
headerCloseMenuButton.classList.add("hide-content");
mobileMenuPanel.classList.add("hide-content");
mobileMenuPanel.classList.remove("topbar-mobile-panel");
headerOpenMenuButton.classList.add("topbar-mobile-menu");
headerOpenMenuButton.classList.remove("hide-content");
});
</script>
<!-- END: this line ends content from: inc/topbar.default.html -->
<!-- START: this line starts content from: inc/header.default.html -->
<div class="header">
<a href="../../2011/zucker/index.html">
<img src="../../png/ioccc.png"
alt="IOCCC image by Matt Zucker"
width=300
height=110>
</a>
<h1>The International Obfuscated C Code Contest</h1>
<h2>how.html for 2012/tromp</h2>
</div>
<!-- END: this line ends content from: inc/header.default.html -->
<!-- START: this line starts content from: inc/navbar.up2index.html -->
<div class="navbar">
<a class="Left" href="index.html">&uarr; jump to 2012/tromp/index.html &uarr;</a>
<a class="Right" href="https://validator.w3.org/nu/?doc=https%3A%2F%2Fwww.ioccc.org%2F2012%2Ftromp%2Fhow.html">&#x2713;</a>
</div>
<!-- END: this line ends content from: inc/navbar.up2index.html -->
<!-- START: this line starts content from: inc/before-content.default.html -->
<div class="content" id="content">
<!-- END: this line ends content from: inc/before-content.default.html -->
<!-- START: this line starts content for HTML phase 21 by: bin/pandoc-wrapper.sh via bin/md2html.sh -->
<!-- BEFORE: 1st line of markdown file: 2012/tromp/how.md -->
<h3 id="notice-to-those-who-wish-for-a-greater-challenge">NOTICE to those who wish for a greater challenge:</h3>
<p><strong>If you want a greater challenge, don’t read any further</strong>:
just try to understand the program via the source.</p>
<p>If you get stuck, come back and read below for additional hints and information.</p>
<h1 id="obfuscation">Obfuscation</h1>
<p>The program implements a so called <a href="https://en.wikipedia.org/wiki/Krivine_machine">Krivine
machine</a>, enhanced with a <a href="https://en.wikipedia.org/wiki/BIOS">basic
input/output system</a> and a reference
counting <a href="https://en.wikipedia.org/wiki/Waste_collector">garbage collector</a>. The
Krivine machine is a stepwise transformer of a global state consisting of the
current term, the current environment (a list of closures), and a stack of
continuations (see the 3rd reference for details).</p>
<p>The term space holds <a href="https://en.wikipedia.org/wiki/Lambda_calculus">lambda
calculus</a> terms in the following
format. 0 denotes some form of I/O; the only four occurrences are at:</p>
<pre><code> C=13: recognizes end of a byte
C=20: recognize output of 0 bit
C=21: recognize output of 1 bit
C=end: input list, expanded lazily</code></pre>
<p><code>1</code> denotes a variable, with the next entry its <a href="https://en.wikipedia.org/wiki/De_Bruijn_index">de Bruijn
index</a>.</p>
<p><code>2</code> denotes application with the next entry the size of the term being applied.</p>
<p><code>3</code> denotes lambda abstraction.</p>
<p>A closure consists of the following items:</p>
<ol start="0" type="1">
<li>pointer to the next closure (as part of an environment), or next record on
free list.</li>
<li>reference count.</li>
<li>pointer to environment.</li>
<li>lambda term (index in term space).</li>
</ol>
<p>Here’s what each variable does:</p>
<pre><code> L Lambda term space
m mode: 0 for bits and 7 for bytes
b bits remaining unread in I, -1 on EOF
D Desirable temporary
c continuation context
a active environment pointer
C Current term index
U Ultimate term pointer
u utility entry
B Born to be free-list of closures
I Input character
O Output character
e entry of current term</code></pre>
<p>Here’s what each of the 6 auxiliary functions do:</p>
<pre><code> s variable lookup in active environment with de Bruijn index u
S gets one bit of input, setting b to -1 on EOF or to remaining number of bits in current byte
k copy fragment from string literal holding lambda terms xor 46 into current end of term space
x expand input, adding 11 (resp. 99) entries to term space for bit (resp. byte) mode
p parses BLC-encoded lambda term using S(), stores results in term space and returns length
d decrease reference counter, add record to free list on reaching zero</code></pre>
<hr style="width:10%;text-align:left;margin-left:0">
<p>Jump to: <a href="#">top</a></p>
<!--
Copyright © 1984-2024 by Landon Curt Noll. All Rights Reserved.
You are free to share and adapt this file under the terms of this license:
Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
For more information, see:
https://creativecommons.org/licenses/by-sa/4.0/
-->
<!-- AFTER: last line of markdown file: 2012/tromp/how.md -->
<!-- END: this line ends content for HTML phase 21 by: bin/pandoc-wrapper.sh via bin/md2html.sh -->
<!-- START: this line starts content from: inc/after-content.default.html -->
</div>
<!-- END: this line ends content from: inc/after-content.default.html -->
<!-- START: this line starts content from: inc/footer.default.html -->
<!--
Copyright © 1984-2025 by Landon Curt Noll. All Rights Reserved.
You are free to share and adapt this file under the terms of this license:
Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
For more information, see:
https://creativecommons.org/licenses/by-sa/4.0/
-->
<div class="footer">
<div id="copyright"><h3>Copyright &copy; 1984-2025 by Landon Curt Noll:
<a href="https://creativecommons.org/faq/#what-does-some-rights-reserved-mean"
target="_blank"
rel="license noopener noreferrer">Some Rights Reserved</a></h3>
<p>
This work is <b>licensed by Landon Curt Noll</b> under
<b><a href="https://creativecommons.org/licenses/by-sa/4.0/?ref=chooser-v1"
target="_blank"
rel="license noopener noreferrer"
style="display:inline-block;">CC BY-SA 4.0</a></b>.
<img style="height:22px!important;margin-left:3px;vertical-align:text-bottom;"
src="../../png/cc.png"
alt="cc inside circle symbol">
<img style="height:22px!important;margin-left:3px;vertical-align:text-bottom;"
src="../../png/by.png"
alt="person inside circle symbol">
<img style="height:22px!important;margin-left:3px;vertical-align:text-bottom;"
src="../../png/sa.png"
alt="arrow looping back on itself inside circle symbol"><br>
You should <b>carefully review</b> the
<b><a href="https://creativecommons.org/licenses/by-sa/4.0/legalcode.en"
target="_blank"
rel="license noopener noreferrer">CC BY-SA 4.0 LEGAL CODE</a></b>
before using the licensed material.<br>
You may wish to review the
<b><a href="../../license.html"
target="_blank"
rel="license noopener noreferrer">highlights of some of the key features and terms</a></b>
of <b>CC BY-SA 4.0</b>.<br>
</p>
</div>
<div id="coda"><h3>Coda</h3>
<p>
<a href="https://validator.w3.org/nu/?doc=https%3A%2F%2Fwww.ioccc.org%2F2012%2Ftromp%2Fhow.html" rel="nofollow">Nu HTML check this web page</a><br>
<a href="#top">Jump to top</a> <a href="#content">Jump to Content</a>
</p>
</div>
</div>
<!-- END: this line ends content from: inc/footer.default.html -->
<!-- START: this line starts content from: inc/bottom.default.html -->
</body>
</html>
<!-- END: this line ends content from: inc/bottom.default.html -->
Reference in new issue View Git Blame Copy Permalink