== Step 2-4

For steps 2-4, I calculated all of each process' outgoing nodes, sorted it in
order and used its sorted position as a way to identify which nodes are being
sent.

This saves an extra communication and lets me index the same items for each
loop.

== Step 5

I exchanged data using the unstructured communication approach, doing an
all-to-all transfer.

To read the result efficiently, I tried using the approach given in the slides.
However, this was taking a long time (up to 45 seconds for the 10,000 case) and
I tried using STL's `std::map`. This proved to be orders of magnitude faster