I am a postdoctoral fellow in Professor Christian Schulz's Algorithm Engineering group at Heidelberg University. My research focuses on making hard graph problems tractable in practice using data reduction rules, local search, and graph neural networks. Some of the problems I have worked on include Independent Set, Dominating Set, Graph Coloring, and Graph Partitioning.
Solved solitaire dice games
Play against a computer opponent who is playing perfect solitaire Yatzy. Every expected value shown is a lookup in a precomputed table covering every reachable position. All games utilize the free variant where cells can be filled in any order.
⚄⚅
Maxi Yatzy
Six dice, 20 categories. Unused rolls carry over to later
turns.
⚃
Yatzy
The Scandinavian five-dice game, 15 categories.
⚂
Yahtzee
The US five-dice game, 13 categories, with the joker
rule.
After each game, you get a breakdown showing your performance against the perfect solitaire strategy.
Education
- 2020 – 2024 Ph.D. in Computer Science University of Bergen. Thesis Graph Neural Networks in Algorithm Engineering, supervised by Prof. Dr. Fredrik Manne hdl:11250/3184216
- 2018 – 2020 M.Sc. Software Engineering University of Bergen and Western Norway University of Applied Sciences. Grade A
- 2015 – 2018 B.Sc. Computing Western Norway University of Applied Sciences.
Competitions
- 2026 SISAP Indexing Challenge 2nd Task 1 – All-k-NN (Preliminary results) Leaderboard github.com/henrixapp/sisap2026-plain-local-search
- 2025 PACE Challenge — Dominating Set & Hitting Set 5th Heuristic Track – Dominating Set 5th Heuristic Track – Hitting Set Leaderboard github.com/KennethLangedal/PACE2025
- 2024 PACE Challenge — One-sided Crossing Minimization minimization 1st Parameterized Track 2nd Heuristic Track Leaderboard github.com/KennethLangedal/PACE2024-UiB 10.4230/LIPIcs.IPEC.2024.34
- 2023 PACE Challenge — Twinwidth 2nd Heuristic Track Leaderboard bitbucket/Zygosity 10.4230/LIPIcs.IPEC.2023.39
- 2022 PACE Challenge — Directed Feedback Vertex Set 4th Heuristic Track Leaderboard github.com/KennethLangedal/DFVS
Papers
- 2026 Engineering Learned Heuristics to Improve Clustering for Multilevel Graph Partitioning Simeon Schrape, Nikolai Maas, Kenneth Langedal, Daniel Seemaier International Symposium on Experimental Algorithms (SEA 2026) 10.4230/LIPIcs.SEA.2026.25 github.com/kahypar/mt-kahypar/tree/sea2026
- 2026 A Comprehensive Survey of Data Reduction Rules for the Maximum Weighted Independent Set Problem Ernestine Großmann, Kenneth Langedal, Christian Schulz Technical report arXiv:2412.09303 github.com/KarlsruheMIS/DataReductions
- 2025 Accelerating Reductions Using Graph Neural Networks for the Maximum Weight Independent Set Problem Ernestine Großmann, Kenneth Langedal, Christian Schulz Conference on Applied and Computational Discrete Algorithms (ACDA 2025) 10.1137/1.9781611979084.12 github.com/KarlsruheMIS/DataReductions
- 2025 Concurrent Iterated Local Search for the Maximum Weight Independent Set Problem Ernestine Großmann, Kenneth Langedal, Christian Schulz International Symposium on Experimental Algorithms (SEA 2025) 10.4230/LIPIcs.SEA.2025.22 github.com/KarlsruheMIS/CHILS
- 2025 Graph Neural Networks as Ordering Heuristics for Parallel Graph Coloring Kenneth Langedal, Fredrik Manne Symposium on Algorithm Engineering and Experiments (ALENEX 2025) 10.1137/1.9781611978339.5 github.com/KennethLangedal/GNN-COLORING
- 2024 Targeted Branching for the Maximum Independent Set Problem Using Graph Neural Networks Kenneth Langedal, Demian Hespe, Peter Sanders International Symposium on Experimental Algorithms (SEA 2024) 10.4230/LIPIcs.SEA.2024.20 github.com/KennethLangedal/CutBranching-GNN github.com/KennethLangedal/vc-satreduce-gnn
- 2022 Efficient Minimum Weight Vertex Cover Heuristics using Graph Neural Networks Kenneth Langedal, Johannes Langguth, Fredrik Manne, Daniel Thilo Schroeder International Symposium on Experimental Algorithms (SEA 2022) 10.4230/LIPIcs.SEA.2022.12 github.com/KennethLangedal/GNN-MWVC
Solver descriptions and reports
- 2024 PACE Solver Description: LUNCH — Linear Uncrossing Heuristics Kenneth Langedal, Matthias Bentert, Thorgal Blanco, Pål Grønås Drange International Symposium on Parameterized and Exact Computation (IPEC 2024) 10.4230/LIPIcs.IPEC.2024.34 github.com/KennethLangedal/PACE2024-UiB
- 2024 GNNs for smaller kernels, finding the one rule to reduce them all Kenneth Langedal, Fredrik Manne, Ernestine Großmann, Christian Schulz, Matthias Schimek, Fabian Brandt-Tumescheit Scalable Graph Mining and Learning (Dagstuhl Seminar 23491) 10.4230/DagRep.13.12.1
- 2023 PACE Solver Description: Zygosity Emmanuel Arrighi, Pål Grønås Drange, Kenneth Langedal, Farhad Vadiee, Martin Vatshelle, Petra Wolf International Symposium on Parameterized and Exact Computation (IPEC 2023) 10.4230/LIPIcs.IPEC.2023.39 bitbucket/Zygosity
Teaching
- Apr 2026 – Jul 2026 Algorithm Engineering Master-level lecture. Co-instructed with Ernestine Großmann and Christian Schulz, shared equally
- Oct 2025 – Feb 2026 Algorithms and Data Structures II Bachelor-level lecture. Co-instructed with Ernestine Großmann, shared equally
- Apr 2025 – Jul 2025 Distributed and Parallel Algorithms Master-level lecture. Co-instructed with Ernestine Großmann, shared equally
Co-supervised students
- Sep 2025 Engineering Fast Maximum Flows to Speed Up Critical Weighted Independent Set Reductions Markus Everling, bachelor thesis PDF
- Sep 2025 Engineering Good Upper Bounds for the Maximum Weight Independent Set Problem Raphael Heuberger, bachelor thesis PDF
- Apr 2025 Combining Known Techniques to Solve the Dominating Set Problem in Practice Marlon Dittes, bachelor thesis PDF
- Mar 2025 Improving Coarsening for Multilevel Graph Partitioning via Machine Learning Simeon Schrape, bachelor thesis PDF
Work experience
- Mar 2025 – now Heidelberg University Postdoctoral fellow, algorithm engineering group of Prof. Dr. Christian Schulz
- Jan 2025 University of Bergen External examiner for INF113 Fall-2024
- Aug 2016 – Aug 2024 Western Norway University of Applied Sciences External examiner for ING202 Fall-2024, DAT102 Spring-2024 and ING201 Spring-2023. Group leader in DAT100, DAT103, DAT154, DAT158 and MAT108 from 2016 to 2020
- Aug 2018 – Jun 2020 Hop Oppveksttun middle school Teacher for the elective programming course, 9th and 10th grade
- Feb 2019 – Aug 2019 Ai Innovation Center AS Consultant
- Jun 2017 – Aug 2018 OneSubsea Summer internships doing software engineering
- Aug 2013 – Oct 2018 Mildeheimen nursing home Part-time (13%) over five years as a nursing assistant
- Jul 2014 – Jul 2015 Royal Norwegian Navy Conscription
Service
- Reviewer
- SOFSEM 2026, IPEC 2025, ESA 2025, SWAT 2024, Nature Communications
- Programme committee
- CompAI 2025
- Funding
- NORA National Research School for AI, project 331723, 30 000 NOK
Meltzer Research Fund, project 104066111, 18 700 NOK - Doctoral coursework
- Supercomputing Algorithms, Parallel Programming, Deep Learning
- Languages
- C and C++ with OpenMP/MPI by preference. Also x86 assembly, Java, C#, JavaScript, Python, SQL and Haskell