Reach-ability in graphs is quite an interesting topic in applied sciences. For example, recently I had to figure out (nontrivial) investment proportions in fun

Reach-ability in graphs is quite an interesting topic in applied sciences. For example, recently I had to figure out (nontrivial) investment proportions in funds and realised two things: 1. You can use a weighted DAG [1] and sum the products of paths from each leaf to the root to get to the investment proportions; the total of all such paths from leaves to the root should be 100% of the underlying investing entities. 2. Tax offices should use weighted DAGs to figure out cases where there is suspected fraud. Whenever you sum and don't get to 100%, then you know that people are doing fishy things with their investment vehicles and shell companies. [2] [1] https://en.wikipedia.org/wiki/Daw https://en.wikipedia.org/wiki/Daw [2] https://en.m.wikipedia.org/wiki/CumEx-Files https://en.m.wikipedia.org/wiki/CumEx-Files