GP of Ekateinburg has just finished. Let's discuss problems here. How to solve H?
(Russian version of the post contains my anger about statements).
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Problem H: https://en.wikipedia.org/wiki/Schreier%E2%80%93Sims_algorithm
Well, is it allowed to use such tasks in contests? This task is just a copy of Schreier and Sims' idea and there is zero originality. I hope authors to come up with original tasks.
And problem I — I believe it's not a good idea to try to separate MCMF and Hungarian. Both are O(n^3).
MCMF worked 0.336 seconds in my case, not even close to TL (and I believe it can be still optimized a lot, by changing long long to int etc.).
Interesting fact: most of the people who had issues with MCMF fitting into the time limit never have issues with
long long.Were they actually trying to separate them though? I passed with Dijkstra on Set in my Min Cost Flow. So it was even O(N^3logN).
OK maybe my implementation was bad — is O(E log E) dijkstra faster than O(V^2) in practice?
With set: 1.2s
V^2: 0.49s
MCMF with Ford-Bellman works 0.8
Non-deterministic?
where can see the problems?