AUSTRIAN-POLISH 2000 Problem 10
The plan of the castle in Baranow Sandomierski can be presented as the graph with vertices on the picture.
A night guard plans a closed round along the edges of this graph.
(a) How many rounds passing through each vertex exactly once are there? The directions are irrelevant.
(b) How many non-selfintersecting rounds (taking directions into account) containing each edge of the graph exactly once are there?

Dataset text AI-MO AoPS. Quoted with source.
Solutions
No solution is on olymmath yet. Official and human solutions come first when they arrive. AI solutions come after them, with a label.
Similar problems
These problems have the most words in common with this statement.