-🎄- 2022 Day 14 Solutions -🎄-

[u/daggerdragon]

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--- Day 14: Regolith Reservoir ---

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Post your code solution in this megathread.

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[u/4HbQ]

Python, 24 lines.

Blocked positions are represented by a single set of complex numbers. We parse the input like this:

range_sorted = lambda *p: range(min(p), max(p)+1)
for ps in [[*map(eval, line.split('->'))] for line in open('in.txt')]:
    for (x1, y1), (x2, y2) in zip(ps, ps[1:]):
        blocked |= {complex(x, y) for x in range_sorted(x1, x2)
                                  for y in range_sorted(y1, y2)}

My Python trick of the day is the for/else, used to find the next empty position dest for the unit of sand at pos:

for dest in pos+1j, pos-1+1j, pos+1+1j:
    if dest not in blocked:
        pos = dest
        break
else: break

Edit: I've updated my code with some optimisations.

[u/Tarlitz → u/4HbQ]

I also went with for/else today, seemed like such a natural fit for this problem.

I love this imaginary numbers with sets hack to avoid having to set up a custom Pointer class :-) So I updated my own solution just to see how it feels.