http://www.spoj.pl/problems/NOTOKNOT/
Wiki:
http://en.wikipedia.org/wiki/Unknotting_problem
http://en.wikipedia.org/wiki/Regina_(program)
Discuss:
I have try to solve this problem for more than half a month. Read all the book I can found in the local Library and I can't even find a direction !...
Is there a polynomial complexity algorithm or only have a physical simulation algorithm ? ... I was particularly interested in the matter, any one can guide me a correct direction ~~
Thanks a lot!..