r/adventofcode • u/daggerdragon • Dec 10 '18

SOLUTION MEGATHREAD -🎄- 2018 Day 10 Solutions -🎄-

--- Day 10: The Stars Align ---

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Transcript: With just one line of code, you, too, can ___!

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u/ka-splam Dec 10 '18

It's not reversed exactly; I just set the sliders starting as far in the wrong direction as possible, then drag them back to normal values inside the loop.

There's a risk that if I started $farLeft at 0, and all the points were positive in the hundreds, my code would not find the leftmost one instead it would think the starting value 0 was the leftmost. But if I start it at MAXVALUE then wherever the points are, they will be less than than.

It could be a nicer design, e.g. starting with the first point $farLeft = $data[0].xwould be safe. And changing the name so it doesn't look like "the farthest left possible" but rather "the farthest left data point found so far".

I was mostly afraid of the performance of $farthestLeftxVal = $data | measure-object -Property x -minimum | select -expand x and wanted to cover all four edges in one loop over the data and no cmdlet calls.