As I promised to Starfish, I will write something about how to read and write files in matlab. Since I just picked up this part recently, there maybe some mistakes. Frankly speaking, I write this half for some one who may need it, half for myself, because I may forget them in the future, haha. [...]

http://www2.austin.cc.tx.us/powens/+Topics/HTML/05-6/05-6.html http://planetmath.org/encyclopedia/FleurysAlgorithm.html http://www.ctl.ua.edu/math103/euler/ifagraph.htm I prefer the first one because there is an example. Fleury’s Algorithm is used to find the Eulerian Cycle (if there is one) or the Eulerian Path (if there is no Eulerian Cycle). The computation complexity is O(n^4). There is another O(n+e) algorithm which uses the cycles.