---
categories: Graph theory, Graph algorithms, Combinatorial optimization
---

## Problems
- [Freckles](https://open.kattis.com/problems/freckles)
- [Minimum Spanning Tree](https://open.kattis.com/problems/minspantree)
- [A Feast For Cats](https://open.kattis.com/problems/cats)
- [Arctic Network](https://open.kattis.com/problems/arcticnetwork)
- [Killing Aliens in a Borg maze](https://open.kattis.com/problems/borg)
- [Edges in MST](http://codeforces.com/contest/160/problem/D) [^1]
- [Particle Swapping](https://open.kattis.com/problems/particles)

## See also
- [Union-find data structure]()
- [Minimum Cost Arborescence]()
- [Rectilinear minimum spanning tree]()

## External links
- [Minimum Spanning Tree Tutorial](https://www.hackerearth.com/practice/algorithms/graphs/minimum-spanning-tree/tutorial/)

[^1]: <http://codeforces.com/blog/entry/4108>