Submissions will be ranked by the following methods. In all tracks, if the output of your program turns out to be not a valid contraction sequence, your program will be disqualified. Furthermore, your submission will be disqualified from the exact and parameterized track if a non-optimal solution is output.
Exact Track & Parameterized Track
You will be ranked by the number of solved instances. In case of a tie, the winner is determined by the total time spent on the solved instances. In particular, there is no need to abort a “hopeless” run early.
Heuristic Track
You will be ranked by the sum
over all instances of (PC #crossings) / (your #crossings).
Here, (your #crossings) is the number of crossings in
your submission and (PC #crossings) is the number of crossings in
the best solution known to the PC
(which may not be optimal and may decrease in the course of the contest).
If there is a crossing-free solution, then you receive 1 point if you find it and 0 points if your solution has crossings.
Note that the optil.io platform ranking differs here, as we cannot input a custom scoring function. On optil.io, the best solution gets a score of 1, the worst solution a score of 0, and there’s a linear score scale for solutions with a crossing number between these values. The correct score can be seen on the results page.
Final Score
Since the hardware on optil.io is not reliable and can provide different results upon uploading the same solver, we will compute the final score on our own hardware. Note that this hardware is slightly stronger than the one on optil.io: They use Intel(R) Xeon(R) CPU E5-2695 v3 computing cores at 2.30GHz, while we will use Intel(R) Xeon(R) Gold CPU 6342 computing cores at 2.80GHz.