3 ms·

https://en.wikipedia.org/wiki/Kirchhoff%27s_theorem https://en.wikipedia.org/wiki/Kirchhoff%27s_theorem ?

• kmill 11y ago
  Implementation: https://gist.github.com/kmill/f4f47913d036fce687bc https://gist.github.com/kmill/f4f47913d036fce687bc Though it counts reflections as distinct.
• ginko 11y ago
  It surprised me that he even mentioned the concept of a spanning tree, yet didn't use it for more than a coarse upper bound.