Entries Tagged 'Entertainment' ↓

Do you like Sudoku? If so, check out my Sudoku Helper! I wrote it to help you solve Sudoku puzzles by just giving you a hint of what the numbers could be, instead of just telling you the answer. This way you can still enjoy the game!

It works by having you enter in the numbers in the column and row that intersect at the square you are stuck on. Additionally you can enter in the numbers that are filled in for that 3×3 square. The Sudoku Helper will then tell you what numbers could be in the square.

Give it a try! Sometimes the best strategy is to get a hint, not the final answer. Hopefully you’ll find this helpful!

Sudoku Helper

I had the Petit DosBox from OS X up and running a while ago, but today when I went to run it I kept getting an error about libSDL not being found.

Last year I had an “incident” that basically required me to re-run the 10.4 installation. I think when I did that it must have wiped out the symbolic link I had made to get Petit to run. If you are finding yourself in this situation, here’s what I did to get it up and running (Mac Mini running OS X10.4.5):

WARNING: Only attempt this if you are confident of your computer skills *and* you have backups of your important data. This is a fairly safe thing I’m describing, but you are doing it at your own risk. I’m merely pointing out what I did and how it worked for me. Your mileage may vary. Proceed at your own risk.

1. Open up a terminal window.
2. Type in cd /usr/local/lib and press return.
3. Type in ls and press return. Odds are there is nothing there.
4. If you don’t see anything that says SDL, type this in: sudo su and press return
5. Enter your system password. (Basically you are going to run as root for this next command)
6. Your prompt should now say “root”. Type in (or cut-n-paste) this line: ln -s /sw/lib/libSDL-1.2.0.dylib libSDL-1.2.0.dylib and press return.
7. Type in ls and press return. You should now see libSDL-1.2.0.dylib. At this point try running any Petit dos program. If it works, yaa! If not, you might be missing the SDL installation. I’m not sure if it comes with the Mac by default or ifI had installed it manually.

If you have success or failure with these instructions, please leave a message in the comments. I’ll try to help out if I can (but no guarantees).

Dr. Dobb’s magazine this month has an article entitled “Sudoku & Graph Theory” which caught my eye. The article describes a logical Sudoku solver the authors built that uses graph theory techniques to analyze the puzzle.

This really got my attention because graph theory is an important field of mathematics that has a number of applications (network traffic flows for example), and it is something that I’m always interested to learn more about.

The first thing the article does is assume the 81 cells of a sudoku puzzle represent a vertex on a graph. They then point out that the numbers that can be assigned to each row, column, or 3×3 square can be thought of as a node of a bipartite graph. That node contains a array of numbers that could possibly be in that position on the puzzle.

This is exactly what I do when trying to solve a sudoku puzzle, but expressed in mathematical/topological terms. (This is what I was trying to get across in my post about Sudoku Strategy.)

The article then goes on to present two methods of logically eliminating number from the array to find the correct answer: Pile Exclusion and Chain Exclusion. Sadly, I can not find any links on the web to explain these algorithms in more detail, but the article does an ok job of showing how they work.

I do want to point out that if you read the full article, beware that the sample sudoku puzzle they present does not seem to match up with the sample arrays (or vectors as they call them) when they are demonstrating the chain and pile exclusions!

My own personal preference seems to be the Pile Exclusion, that seems to match up with how I solve puzzles. It is basically a system where you find groups of numbers that are common across several squares (usually in a 3×3 section, but I often expand it to include the row and column). Usually this works out so that you have two squares where the numbers could be 1,3,7 in one and 1,7 in the other. Then you look at the other squares and if you see that 1 and 7 aren’t a choice in any of them, then 1 and 7 must be in the two squares you are looking at. This means that the 3 is not a possible answer, so you can mark it out. This usually winds up helping you figure out where the 3 is supposed to go.

The Chain Exclusion is similar in that you are looking for groupings of numbers, but with this algorithm you are looking for the numbers to be shared in other parts of the array in order to rule out other locations. For example, if you have 1,3 and 3,4 and 4,1 as the possible answers in three cells, then other locations in the puzzle that contain a 3 can be ruled out. Personally I find the Chain Exclusion method to be more of a leap than the Pile Exclusion.

Both of these methods basically boil down to using logic to reduce (or outright find) the possible numbers that could be the answer. Using both, as the program written for the article does, makes for a powerful set of tools to work your way through the puzzle. The alternative is to do a “brute force search” which means simply trying every possible number in ever possible cell until you get the solution. Since there are 81 cells and 9 possible numbers per cell that means there are 9^81 possible answers (in plain english this means 19 followed by 76 zeros) give or take a few depending how many numbers were already filled in for you. Needless to say, using Pile and Chain Exclusions will help you get the puzzle solved much sooner.

So go check out the article in the Feb 2006 issue of Dr. Dobb’s magazine, it’s a great read.

Every couple of months there seems to be news about a company that wants to put ads into games. A lot of people are unsure about this, but I think it is a pretty interesting and cool idea.

This past weekend I popped Grand Theft Auto: San Andreas back into the PlayStation and started playing around. I had forgotten how much I liked the radio stations in that game, not only do they play good music (well, most of them do), but the fake ads that are in the game are hilarious.

I’m not saying that companies should put those kinds of ads in the game (after all, what company is going to pay to have a commercial that makes fun of them?), but slipping in a “This block of songs is brought to you by Coke!” now and then would be pretty cool and would make the game more “real” because, that’s what DJ’s do in real life.

More interesting I think would be to have ads on billboards in the game. There are already billboards all over the place, imagine if every 5th or 10th had a real ad in it? And what if the ads rotated through the city every few game-days? That would add a sense of a “living city” to the game play, which I think is a major component of the appeal of MMORPG’s. An example of this today is SSX: On Tour, which has several real-world product ads sprinkled in it.

Plus in this day and age of increasingly interconnected devices, I can see where a game company could offer to update the ads every few weeks/months via game updates. That would be really interesting to see, but I think it might not really happen. Most games are really really popular for the first few weeks or months after their release, but then they tend to drop off the gamer’s screens for various reasons. It would probably be hard to sell ad space on a game like GTA:SA when the next big game pops out.

A final note: I’m not saying all games should have ads. A game set in ancient Rome would not have billboards advertising the latest release from 50 Cent. That’s common sense. But a racing game set in a big city… That’s quite an opportunity.

Today I decided to do something about a project that has been nagging me. I started write a game last year (or was it 2004? It was started a while ago at any rate…), but then I just stopped working on it for a variety of reasons.

One of the biggest reason was that my design, while it sounded good in theory, wasn’t working out too well in practice. My idea was to make a Wasteland style RPG type of game that used a state machine to control the game. The idea worked pretty well in the beginning. I found a project that was similar to what I wanted to do, then adapted the code and put a state engine in there to drive everything.

It worked well enough until I wanted to add in more features like events, changing maps, etc. Then the code revealed how convoluted it was. A lot if it is my fault, I’m still not in the “Python frame of mind” for everything I do, and that has made things more difficult. I checked around on the internet to see if anyone else was tackling a project like this and lo-and-behold there was. This site has a great little tutorial that pretty much covers everything I wanted to do, but done without an (explicit) state machine.

Instead it uses a different pattern, the mediator. The mediator looks a lot like the observer pattern, at this point I’m not sure what the major difference between them is. At any rate, I had some time today so I set out to refactor my little game and see if I could drop in the mediator/observer pattern in the place of the state machine.

Much to my surprise and delight, it was fairly easy to do. After about 3 hours or so of work I’m now almost at the same point (functionality-wise) that the original code was. At first glance it looks like I’ve streamlined my code base a lot and can eliminate a lot of extra code that was introduced to the system. The only downside I can see so far is it looks like the mediator/observer based code is inefficient in that every game object gets called every game tick. At this point I’ve got a pretty small number of objects, but the moment I get NPC’s and inventory items working I’m going to have to do something because that will introduce a ton of objects to the game world. Truthfully I don’t think it will be too terribly hard, but it is something to think about (the web page mentions this problem and has a few suggestions).

The biggest and nicest advantage of this refactoring has to be the separation that has been gained. Before I was using global objects to try and keep everything in touch with everything else. Now each game object is its own little island, knowing about only those objects it needs to know about. This is really exciting for me, before I was dreading adding new things to the game world because of the work that was involved in attaching them to everything.

Well, back to the salt mines, let me see if I can make some more progress!

For the most part, Podcasts don’t do a lot for me. That makes me feel kinda sad because I really like the idea of Podcasting, and I’m already listening to my iPod in the car, so it seems like a natural fit. I’ve only listened to about 4 or 5 podcasts, and with one exception they really haven’t captured me like I thought they would.

The exception is The Escape Pod which is a weekly sci-fi short story podcast. Most of the stories that are read are pretty good, and the host Steve Eley does a good job of presenting the show (and reading/performing the stories). If you are into sci-fi or even just good stories swing by and check them out. I found the podcast through iTunes a while back and its the only podcast I still subscribe to. And after listening to several podcasts back to back, Steve’s suggestion to blog about the Escape Pod finally worked.

I’ve been reading a ton of books lately and I decided I would start reviewing them in case anyone wonders what I think (or what I’ve been reading lately). Check it out: Katie And Nick’s Reviews

I’m pretty much going to review anything I can think of like music, books, and movies. Drop on by and take a look!

I was thinking of doing an article about Sudoko and my strategy for solving them, but a quick check on the MAA.org website lead me to an article which eventually lead me to Sudoku.com where there are several pages of strategy.

I read through them quickly and for the most part that site does what I do to solve them, but it explains it in a weird way (at least that’s what I thought). Maybe this will inspire me to do my own “how to win” page.

UPDATE: I made a page that help you solve sudoku puzzles by giving you hints. Check it out: Sudoku Helper

I’ve mentioned it before, and once again TiVo delivered the goods. Another episode of Metal Mania and another Dokken video. This time it was “Breaking the chains” and whoa, it was something else.

When I saw that interview with Jeff Pilson and he made that comment about cheesey videos, he must have been talking about this one. It was dripping with 80’s cheese.

But Jeff shouldn’t feel too bad, I also saw a video from Europe and Dio’s Holy Diver. Holy crap, that was cheesey.

But hey, metal video are supposed to be cheesey. And that’s what makes them so metal.

This article begins to cover the many reasons why I feel The Amazing Race is going downhill. ‘Amazing Race’ has lost its way - REALITY TV - MSNBC.com

It used to be a pretty good show, but now it seems to be pandering to a very low denominator, and that is sad. Its like they (the producers and the network) are saying “Hey, we need big ratings for this show, what can we do to clone our other shows to make this one just like them.”

Its like original ideas are forbidden in Hollywood.