binstretch
Computing lower bounds for Online Bin Stretching in C.
This is a companion source code to the paper "Online Bin Stretching with Three Bins" by Martin Böhm, Jiří Sgall, Rob van Stee and Pavel Veselý, which is to be submitted for publication. The code implements a minimax game tree search for lower bounds on Online Bin Stretching in C, using dynamic programming and extensive caching.
The code is using a technique first presented in the following paper:
The lower bound search of the paper is available on Github.
We build on their approach while improving the implementation both technically and conceptually, which allowed us to find a better lower bound of 45/33 for three bins as well as a first bound of 19/14 for four bins and five bins. (Note that an updated version of the Gabay, Brauner, Kotov paper from June 2015 independently shows the lower bound of 19/14 for four bins as well.)