add notices to those who wish for a greater challenge

We add the following level-3 header to help people identify text
they may wish to skip if they wish for a greater challenge:

```
```

After that notice we add:

```
**If you want a greater challenge, don't read any further**:
just try to understand the program via the source.

If you get stuck, come back and read below for additional hints and information.
```

And sometimes follow with:

```
```

Or sometimes follow with:

```
```

Where the alt code impacts a "greater challenge", we add instead:

```
**If you want a greater challenge, don't read any further**:
just try to understand the program without looking at the Alternate code.

If you get stuck, come back and look at the Alternate code.
```

And where a given command impacts a "greater challenge", we add instead:

```
**If you want a greater challenge, don't read any further**:
just try to understand the program without running the command below.

If you get stuck, come back and run the following command:
```

Perform `make www` to perform the above and test under macOS.

2015/burton/README.md

@@ -228,10 +228,19 @@ This allows for a convenient test suite:
 ```
 
 
+### NOTICE to those who wish for a greater challenge
+
+**If you want a greater challenge, don't read any further**:
+just try to understand the program via the source.
+
+If you get stuck, come back and read below for additional hints and information.
+
+
 ### Obfuscation:
 
 If you do not want to puzzle out how it works, see [obfuscation.html](obfuscation.html).
 
+
 <!--
 
     Copyright © 1984-2024 by Landon Curt Noll. All Rights Reserved.

2015/burton/index.html

@@ -528,6 +528,10 @@ To stifle these complaints:</p>
 This allows for a convenient test suite:</p>
 <pre><code>    ln -sf prog eprog
     PATH=. eprog &lt; test.in | diff - test.out</code></pre>
+<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>
 <h3 id="obfuscation">Obfuscation:</h3>
 <p>If you do not want to puzzle out how it works, see <a href="obfuscation.html">obfuscation.html</a>.</p>
 <!--

2015/dogon/README.md

@@ -204,6 +204,14 @@ X86 architectures indeed SSE/AVX is used for the long longs.  Following is some
 obfuscation information, So if you want to play tough, stop reading at this point.
 
 
+### NOTICE to those who wish for a greater challenge
+
+**If you want a greater challenge, don't read any further**:
+just try to understand the program via the source.
+
+If you get stuck, come back and read below for additional hints and information.
+
+
 ### Portable SIMD programming:
 
 So how is this done? Quite simply by using the whole `long long` arithmetic's

2015/dogon/index.html

@@ -527,6 +527,10 @@ in a portable way without ever using any SSE/AVX or other non-portable compiler
 inline functions! The irony though, is that when compiling the program on modern
 X86 architectures indeed SSE/AVX is used for the long longs. Following is some
 obfuscation information, So if you want to play tough, stop reading at this point.</p>
+<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>
 <h3 id="portable-simd-programming">Portable SIMD programming:</h3>
 <p>So how is this done? Quite simply by using the whole <code>long long</code> arithmetic’s
 capability. I think the C99 standard assures us that <code>long long</code> has at least 64

2015/endoh3/README.md

@@ -64,7 +64,15 @@ the source code from all angles..
 * Find `main()` function.
 
 
-### Spoiler
+### NOTICE to those who wish for a greater challenge
+
+**If you want a greater challenge, don't read any further**:
+just try to understand the program via the source.
+
+If you get stuck, come back and read below for additional hints and information.
+
+
+### What this entry does:
 
 This program is a joke PDP-11 emulator.  ("ll-dpd" is embedded in the code.
 Read it upside down.)
@@ -80,7 +88,7 @@ You got it?  This program is supposed to be used in this way:
 You can enjoy the legendary winning entry of the first IOCCC, again.
 
 
-### Internal
+### How this entry works:
 
 This program uses `__attribute__((constructor))`, which is a GCC extension, to
 hijack the `main()` function call.  And then it interprets `main()` as an

2015/endoh3/index.html

@@ -438,7 +438,11 @@ the same reason. But I believe it is reasonably portable.</li>
 the source code from all angles..</li>
 <li>Find <code>main()</code> function.</li>
 </ul>
-<h3 id="spoiler">Spoiler</h3>
+<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>
+<h3 id="what-this-entry-does">What this entry does:</h3>
 <p>This program is a joke PDP-11 emulator. (“ll-dpd” is embedded in the code.
 Read it upside down.)</p>
 <p>You got it? This program is supposed to be used in this way:</p>
@@ -446,7 +450,7 @@ Read it upside down.)</p>
     clang -o prog prog.c mullender.c
     ./prog</code></pre>
 <p>You can enjoy the legendary winning entry of the first IOCCC, again.</p>
-<h3 id="internal">Internal</h3>
+<h3 id="how-this-entry-works">How this entry works:</h3>
 <p>This program uses <code>__attribute__((constructor))</code>, which is a GCC extension, to
 hijack the <code>main()</code> function call. And then it interprets <code>main()</code> as an
 instruction sequence.</p>