CMO 2010 Problem 4
- Paper
Each vertex of a finite graph can be colored either black or white. Initially all vertices are black. We are allowed to pick a vertex and change the color of and all of its neighbours. Is it possible to change the colour of every vertex from black to white by a sequence of operations of this type?
Dataset text NuminaMath olympiads. 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.