For question 3a, here ( ), I get that the "sticks" that are higher up, as in sticking out of the page, are like nodes on a graph that have directed edges pointing to the "sticks" below, as in into the page.

If I look at the answer from the solutions PDF ( ), it makes sense to me, but how would I do this systematically? For example, if it were drawn as a regular graph, one could use Kosaraju's algorithm ( ), but the question suggests not drawing the graph. Is it expecting that the question be answered merely by eyeballing things? What should one do in order to properly answer this question?

Any input would be GREATLY appreciated!