2025/uellenberg - Ping pong prize
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The International Obfuscated C Code Contest
2025/uellenberg - Ping pong prize
Quine pong
← 2025/tompng<br>↑ 2025 ↑<br>2025/yang1 →<br>C code<br>Makefile<br>Inventory<br>Original C
Author:
Name: Jonah Uellenberg
Location: US - United States of America (United States)
Award: Ping pong prize
To build:
make all<br>To use:
./prog | tee prog1.c | cc -xc -o prog1 - ; ./prog1 | diff - prog1.c<br>Try:
./try.sh<br>Alternate code:
Alternate build:
make prog.alt<br>Alternate use:
./prog.alt | tee prog1.alt.c | cc -xc -o prog1.alt - ; ./prog1.alt | diff - prog1.alt.c<br>Judges’ remarks:
This presses so many of our buttons, not just W and E!
Nevertheless, please resist the urge to write “Quine Doom” as a next year’s<br>IOCCC submission.
A fun challenge
Please checkout the fun challenge(s) for this winning entry.
Author’s remarks:
Quine Pong
This is my version of pong with a killer upgrade - it requires a C compiler<br>to use! Running the program produces the source code to generate the next<br>frame, formatted to display the current frame. By repeatedly compiling<br>and running each successive frame, you can play the game. To move,<br>pass either “w” (up) or “e” (down) as an argument. You play as the<br>paddle on the right, and your opponent is the computer. If you don’t<br>love the thought of running the same commands over and over again ( :(<br>), you can just run try.sh, which automates this process and lets you<br>interact directly using your keyboard.
Make sure you win against the computer at least once, there’s a fun<br>surprise waiting for you (spoilers in the next section)! Go on, go play<br>the game, I’ll still be waiting for you when you return.
Now that all the obfuscated C fans are distracted, it’s time I<br>let you in on what’s really going on. See, this code isn’t really<br>obfuscated. It never was. No, it’s compiled . That’s right, not a<br>single nibble desecrated by human hands, only purified in the unfeeling<br>steel of liveness analysis, constant folding, variable reallocation,<br>and compile-time evaluation. And the best part? There’s a source file<br>out there, just waiting to be read. Comprehendible variable names,<br>comments explaining the justification for every block of code, and not<br>a magic number in sight (well, maybe a few - no one’s perfect). Imagine<br>that! Don’t believe me? Let me show you.
If you want to take a closer look at the code, prog.c<br>is the obfuscated version of the code, prog.alt.c is<br>a version with indentation and newlines and without define compression<br>(which you can run with try.alt.sh), and prog.int contains<br>the original source code. prog.alt.c is also a quine, and is otherwise<br>identical to prog.c except for formatting, although it’s very long and<br>doesn’t fit well in terminal windows, so playing it is difficult. The quine<br>compiler is available at https://github.com/uellenberg/Insert, which<br>you can use to modify the program and create your own quines!
I’ve been informed that going into too much depth on how the obfuscated<br>code works can be considered condescending, and considering that I’ve<br>already directed you to the non-obfuscated source code, I have to assume<br>that any mention of functionality will cause you to implode under the<br>sheer rudeness of it all. So, I’ll instead be talking mostly about<br>the compiler, and some of the fun tricks that I’ve implemented to make<br>the output smaller. There are a lot of optimizations, so I’ll skip over<br>everything typical of a boring compiler (such as gcc, which you probably<br>used to run it - or maybe you’re a clang person, I don’t know).
The one thing I will go into more detail on is that the second jumping<br>game is actually a modified version of pong, and heavily uses its<br>code to save on size, including the collision, quine update/printing,<br>and display code (although I like to imagine that in the jumping game,<br>the ball is actually a dinosaur and the paddles are cacti).
This is inspired by the work of Yusuke Endoh, especially his self-similar<br>quine. The programs he’s created are magnificent, and are what originally<br>got me interested in quines.
Usage
I recommend running try.sh and try.alt.sh, as they allow you to play the<br>game in real-time. Once the game is running, just press “w” to go up<br>and “e” to go down. Note: I’ve only tested this under Linux, and your<br>terminal must be at least 70 characters wide and 60 characters tall,<br>otherwise the formatting won’t display correctly and/or you won’t have<br>the full game in frame. You can also remove the “cp prog.c prog.quine.c”<br>from try.sh, which will make it resume...