Variations for spanning trees

Coursebooks discussing graph algorithms usually have a chapter on minimum spanning trees. It usually contains Prim's and Kruskal's algorithms [1, 21 but often lacks other applications. This type of problem is rarely present at informatics competitions or in tests in secondary or higher level informatics education This article is aimed at describing some competition tasks that help us prove that the application of the above algorithms are well-suited for both competition and evil:him:km purposes.