Wednesday, 27 February 2013

Return of the Four Fours

In an attempt to get faster results for the four fours problem mentioned earlier, I've come up with a simpler algorithm that does even more number crunching but somehow computes the precious list faster. Despite being sillier because it computes the same thing twice (or even worse), it'll use waaay less memory.
Oh, and since the algorithm encodes the solutions as stacks of operations, it'll print them accordingly (in reverse polish notation).

I want to see all

Friday, 15 February 2013

Four fours

The "Four fours" problem has probably wasted many people's time... As I recently rediscovered the fun in solving this, but I didn't have the patience to figure out how to get more than 2 or 3 values, I started writing a program for it instead. Supposedly, computers are better at number crunching.

It takes about 2 15 seconds to compute five fours on my super-speedy 1.0 GHz AMD not-even-sure-it's-Turing-complete thing. However, trying with seven fours is only for the brave and the patient. The algorithm stores partial results in some huge matrix to reduce computation time, but I have a feeling that this has consequences (especially in JavaScript).

I want to see all