A Chrome-8 update is now approved and released in the AppStore. This release contains hints! Try it!

Thanks,

/M

Developing iPhone apps: SeaZone RC, Chrome-8

Just received news that Canadian Pacific will standardize on Prover iLock for Interlocking System Design, Simulation and Formal Verification. Prover iLock is a product by Prover Technology, the company I co-founded many years ago.

Way to go guys!

/M

Chrome-8 can now show hints in Master mode. I’ve received many requests for this feature and it is also the only “con” AppSpy found when reviewing Chrome-8.

Now Chrome-8 8.4 is submitted for review, and will normally be released within a few days. Check it out at the AppStore!

/M

Since there are so many good sources defining NP-complete (see below) I will just give my “elevator pitch”.

To say that a problem is NP-complete means that there is no *known* way of efficiently computing answers to the problem in general. There will always be a worst case when the computation will require exponential time to finish. However, given any proposed *solution* to an NP-complete problem, it is possible to efficiently check whether the solution is correct or not. A popular example is the Traveling Salesman Problem (TSP) which is the problem of computing the cheapest way to visit, say, all major cities in the USA for any given timetable and cost.

Showing that a problem is NP-complete involves finding an efficient translation of the problem into a known NP-complete problem.

There are many problems that are found to be NP-complete, for instance Graph Coloring, the basis for my puzzle Chrome-8.

Here’s a short list of references:

- Garey, M. R. and Johnson, D. S. Computers and Intractability: A Guide to the Theory of NP-Completeness. New York: W. H. Freeman, 1983.
- Wikipedia
- Scott Aaronson. NP-complete Problems and Physical Reality

Have fun!

/M

I think “Kometen”, by my fellow countrymen Erik Svedäng and Niklas Åkerblad, promises a very different and nice experience. Check out the trailer.

Check out Chrome-8’s updated site.

/M

Check out this review of Chrome-8 at AppSpy!

/M

There has been a dramatic increase in traffic to the Chrome-8 web site since yesterday. I’m going to find out why.

/M

Time to start work on the apps for iPhone OS 4 coming out this June! I need to skip a few maintenance releases of Chrome-8 in order to manage. But I’m sure it’s going to be worth wile.

/M