I’m movin

My page/blog is moving to another page:

phimuemue.com

SAT – a randomized algorithm

As everybody knows, SAT is NP-complete.

Here is a randomized algorithm that (eventually) solves an instance of a SAT-Problem (in polynomial time).

A nice method for…

Consider the following Code (in Python):

def dosomething(a, b):
    result=0
    while (a):
        if (a&1):
            result+=b
        b=b<<1
        a=a>>1
    return result

The function needs a to be a positive integer and b to be an integer.

What does the function do? Can you tell how it works?

Some algorithmic quizzes

Many algorithmic puzzles are circulating around the net. Here i want to present some problems i came across and found interesting to solve (or not to solve).

Can you solve it? – Maximum sum

Here i want to present a quite nice small puzzle: Given an array of not necessarily positive numbers (elements are called ), i want to find the indices , , where , so that the sum is maximal.

The task is to find an algorithm that runs in .

Five easy to avoid programming mistakes

When reading source code, i often wonder, why it is so hard to understand. This applies for code from others as well as for my own code i wrote some time ago.

Here are some tipps that could make maintaining and reading your code a bit easier.

Some thoughts on terrain generation

This file provides a general insight in how to generate terrains using the diamond-square algorithm.

You can download the file here. It is just a draft, but i’m offering it here, because i hope it could help somebody.

Logarithm of float numbers

Some time ago, a teacher asked me, how computers logarithmize float numbers.
Of couse, one could use the power series
.
But soon it is clear, that the series converges quite slowly.

The following article gives a general insight how floats could be logarithmized faster. It shows an approximative algorithm that can be extended to get more accurate results.

Erlang

I found a very nice (for me) new programming language: Erlang. It is a concurrent, functional programming language.

“Milestones”

Every programmer has his own personal milestones. Here are some of mine, that were – especially when i began programming – my favourite projects.