advent-of-code/2023-python/output/day_15.py

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from collections import OrderedDict, defaultdict
from output import answer
n = 15
title = "Lens Library"
@answer(1, "Sum of HASH algorithm results: {}")
def part_1(presolved):
return presolved[0]
@answer(2, "Focusing power of the resulting configuration: {}")
def part_2(presolved):
return presolved[1]
def presolve(data):
def h(s):
v = 0
for a in s:
if a == "\n":
continue
v += ord(a)
v *= 17
v = v % 256
return v
p1 = sum(h(c) for c in data.split(","))
b = defaultdict(OrderedDict)
for lr in data.split(","):
if "=" in lr:
l, r = lr.split("=")
if r == "":
continue
k = h(l)
b[k][l] = r
if "-" in lr:
l, _r = lr.split("-")
k = h(l)
if l in b[k]:
del b[k][l]
p2 = 0
for i, c in b.items():
for j, f in enumerate(b[i].values(), 1):
p2 += (i + 1) * j * int(f)
return p1, p2
if __name__ == "__main__":
with open("./input/16.txt", "r") as f:
inp = f.read().strip()
inp = presolve(inp)
a = part_1(inp)
b = part_2(inp)
assert a == 509784
assert b == 230197