I have a large list (around 200k) of element pairs
(e.g. A-B, A-C, B-C, ...). How can I find the largest subset of elements amongst which none are paired?
Example of pairs:
A-B A-C A-F B-C C-D E-F F-G
Here the largest subset would be of size 4, and one of the subsets with size 4 would be: