A really aggressive butterfly net

As I understand it, there is quite a variety of thought within the flat earth community. Some think the earth is semi-infinite, so there is just more earth with no other side. Some people think it's a flat disk with nothing but rock or dirt. Others think it's a snow globe with nothing outside.

Oh, maybe I misunderstood. I would like seeing the diagram on the left if it weren't presented as a way to solve the problem, just as a way to illustrate what's happening on the right.

My main concern is if x is negative, 2x will be to the left of x, and there isn't a way to know that a priori. So from a student's perspective, they'd be really confused half the time when trying to think in terms of the diagram.

If I were a student learning this for the first time, I would find this incredibly confusing for 2x+4=-4. Start at -4, move left four to -8, then... right back to -4? Shouldn't I be at -16 or -12 or something? This assumes you know the relative sizes and positions of things, but you generally don't.

Which latch circuit would you use?

All of my #adventofcode solutions in C++ are available on GitHub (except Day 24 part 2, which I did by hand): github.com/49pctber/adv... #cpp #programming

It was! I got a 30x improvement by indexing into a vector instead of using a map. Now day 22 runs in about a tenth of a second instead of about three seconds: github.com/49pctber/adv... #adventofcode

This is wild. Good work!

I wonder if it would be faster to simply allocate and initialize a giant array for memoization...

Just checking in. How did part 2 go? :)

Oh, interesting. I wouldn't have thought of that, but that makes sense in retrospect.

I was floored by Part 2. Cool solution, though!

Congratulations!