Midsummer Combinatorial Workshop XXVI

July 26 - July 30, 2021, Prague

Programme (tentative)

All lectures take place in room S5 at the building of Charles University, Malostranske namesti 25. The times are only indicative and are subject to change.
Morning Registration
9:10-9:30 Welcome, brief information about program of the workshop
9:30-10:00Pavel ValtrOrientation Preserving Maps of the Square Grid
10:00-10:30Roman NedelaPerfect Matchings in Snarks
10:30-11:00Coffee break
11:00-11:30Winfried HochstattlerIndependent Hyperplanes in Oriented Paving Matroids or How to Define Almost General Position
11:30-12:00Stevo TodorcevicTBA
9:00-9:20Martin BalkoUNCE Day: On the expected number of holes in random point sets
9:20-9:45Hossein MoosaeiUNCE Day: Absolute value equation and its challenges
9:45-10:15Jakub BulinUNCE Day: Studying CSP algorithms using pp-interpretability
10:15-10:45Coffee break
10:45-11:15Martin KouteckyUNCE Day: Parameterized Complexity of Mixed Integer (Linear) Programming
11:15-11:48Endre CsokaApplication-oriented mathematical algorithms for group testing (of COVID)
11:55-12:25Yiting JiangTwin-width and generalized coloring number
12:25-12:55Szymon TorunczykOrdered graphs of bounded twin-width
9:00-9:44Nadav MeirLexicographic products of relational structures
9:45-10:30Andy ZuckerThe Halpern-Lauchli theorem via ultrafilters
10:30-11:00Coffee break
11:00-11:25Matej KonecnyHypertournaments
11:25-11:55Adam BartosKPT for weak Ramsey categories
12:00-12:30Dragan MasulovicDual Ramsey properties for equationally defined classes of algebras
12:30-13:15Aleksandra KwiatkowskaAutomorphism group of the random poset
EveningAn awesome social event
9:00-9:30Johanna WieheA trivariate dichromate polynomial for digraphs
9:30-9:50Andrew GoodallTutte's dichromate for signed graphs
9:50-10:20Peter ZemanTesting isomorphism of bounded leafage chordal graphs is in FPT
10:20-10:50Coffee break
10:50-11:20Vaclav RozhonDistributed Algorithms vs Descriptive Combinatorics
11:20-11:40Dusan KnopApproximating fault tolerant FVS
11:45-12:30Patrice Ossona de MendezDiscrepancy of definable set systems
12:30-13:15Gabor KunMeasurable matchings
9:00-9:30Robert SamalRandom Embedding
9:30-10:00Maja PechTowards the classification of homomorphism-homogeneous oriented graphs
10:00-10:30Bojana PanticTowards the classification of polymorphism-homogeneous oriented graphs
10:30-11:00Coffee break
11:00-11:25David Bradley-WilliamsEPPA minimality: Towards extending partial automorphisms of graphs without wasting any vertices
11:25-11:50Lluis VenaCharacterization of extremal families for the Kruskal-Katena inequality
11:55-12:10Vahideh KeikhaApproximate Convex hull of imprecise points
12:10-12:30Denys BulavkaWeak saturation on hypergraphs
12:30-13:00Jan KratochvilCovers of graphs


The workshop continues the tradition of Prague Combinatorial Workshops held since 1993. Oriented on problems of all fields of graph theory, combinatorics and discrete geometry, it will continue in the spirit and informal working atmosphere of the previous meetings.

The workshop takes place at DIMATIA and the Department of Applied Mathematics of Charles University, Malostranske namesti 25, Prague 1, which is located in a historic building in the center of Old Prague. The workshop is also supported by Computer Science Institute of Charles University.

The workshop participation is by invitation only. Regardless, if you wish to participate, please email the organizers and we will respond to you shortly. In case you need an invitation letter (for example for your visa), please let us know and we will be happy to write one for you.

Coffee breaks and part of the meals are provided by the organizers. However, we will collect a modest fee of EUR 70 towards a fraction of the expenses.

As is the tradition, the program of the workshop is determined from day to day. The afternoons are reserved for discussions and other activities. If you intend to give a talk during the MCW, please let us know a few days in advance.

If you arrive later during the workshop, please register with the secretaries in the room 222 (at the 2nd floor).

On Wednesday afternoon, there will be an awesome social event.

This workshop is part of a project that has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No 810115)


Besides the workshop itself, you are free to use the following facilities of our departments:

If you need anything else, contact the organizers.

Travel info (public transport)

For the public transportation you can buy a 90-minute ticket for 32 CZK or 30-minute for 24 CZK in a newsstand or in a vending machine. The vending machines only accept coins (no credit cards, no paper money).

The ticket needs to be validated (in a magic yellow validating machine with a shining arrow). The validating machines are located inside buses and trams. In the Metro subway system, the machine is located at the entryway to the station.

If you need to find a tram connection, you can use the official website. The department building is located near the tram stop "Malostranske namesti". You can see it from the tram stop. It is this building.

Useful routes:

Airport -> Karolinum Hotel

Karolinum Hotel -> MCW


All e-mail correspondence concerning the workshop (e.g. registration, accommodation) should be directed to mcw@kam.mff.cuni.cz.

organizers: Jaroslav Nesetril, Jan Hubicka, Matej Konecny

Previous Workshops

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