Mittagsseminar (in cooperation with A. Steger, D. Steurer and B. Sudakov)

Date and Time: Tuesday, September 25, 2012, 12:15 pm

Duration: 30 minutes

Location: OAT S15/S16/S17

Speaker: Alexander Pilz (Graz University of Technology)

Flip Distance Between Triangulations of a Simple Polygon is NP-Complete

A flip in a triangulation is the operation of removing one edge of the triangulation and adding a diffrent one such that the resulting graph is again a triangulation. The flip distance between two triangulations is the smallest number of flips that is necessary to transform one triangulation into the other. We show that computing the shortest flip distance between two triangulations of a simple polygon is NP-hard. This complements a recent result that shows NP-hardness of determining the flip distance between two triangulations of a planar point set. For the special case of convex polygons, the problem is equivalent to the rotation distance of binary trees, a central problem which is still open after over 25 years of intensive study. (Joint work with Oswin Aichholzer and Wolfgang Mulzer.)

Upcoming talks     |     All previous talks     |     Talks by speaker     |     Upcoming talks in iCal format (beta version!)

Previous talks by year:   2023  2022  2021  2020  2019  2018  2017  2016  2015  2014  2013  2012  2011  2010  2009  2008  2007  2006  2005  2004  2003  2002  2001  2000  1999  1998  1997  1996  

Information for students and suggested topics for student talks

Automatic MiSe System Software Version 1.4803M   |   admin login