Michael Fogleman

Rush Hour is a 6x6 sliding block puzzle invented by Nob Yoshigahara in the 1970s. It was first sold in the United States in 1996.

I played a clone of this game on my first iPhone several years ago. Recently, I stumbled on the physical incarnation of it and instantly bought it on Amazon for my kids to play. We've been having fun with it, but naturally I was most interested in writing some code to solve the puzzles.

I did more than write a simple puzzle solver. I ended up computing every possible puzzle and built a complete database of every "interesting" starting position. It was quite challenging (and exciting!) so I wrote a whole article about it. Check it out!

I wrote my first chess engine back in college. It didn't play very well because I never really figured out the advanced search techniques. More recently, after a long hiatus, I tried my hand at writing a chess engine again, and Mister Queen is the result. It's pretty weak among computer chess engines, but it can beat me handily. Features include:

• Bitboards and "magic" bitboards for board representation and super-fast move generation.
• Custom, hash-based opening book based on over three million games from the FICS database.
• Zobrist hashing and a transposition table storing exact values and the best move.
• Null move pruning, aspiration windows, iterative deepening, quiescence search.
• Supports the Universal Chess Interface (UCI).
• Passes all perft tests.

David Kopec used Mister Queen in a chess app for the Apple TV! Read what he wrote about that here.

My friend introduced me to a board game called Ricochet Robot (or Rasende Roboter in its original German form). It's a fun game, but I found it even more fun as a programming problem. I implemented the game in Python, including a user interface and a solver. After that, I sped up the solver tremendously by porting it to C. My solver includes several "tricks" that make it quite fast. See these slides for more details.

In the mid 2000s, I often played Scrabble on the Internet Scrabble Club, which was not an official Scrabble website. Thousands of people played online there, but the client was horrible and buggy. I took it upon myself to write my own client, which involved reverse engineering the protocol to communicate with the server. I discovered many security issues (cheating vectors) while doing this. But I just wanted a nice client for playing Scrabble online. I pretty much finished the client, and it worked quite nicely, but it never went much further than that and who knows if it still works.

I wrote TONS of programs in QBasic throughout high school. Most of them are lost forever, but a few have survived. I've put a couple programs, including this one, on the Internet Archive for eternal posterity, and there you can play them in the browser. This is a simple Tetris clone but it even includes a computer player that plays quite well!