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#!/usr/bin/env python3
import aoc20
import sys
def pt1(_in):
constraints = [[range(int((b := a.split("-"))[0]), int(b[1])+1)
for a in line.split(": ")[1].split(" or ")]
for line in _in[:20]]
return sum(sum(int(field)
for field in line.strip().split(",")
if not any(any(int(field) in cons
for cons in constraint)
for constraint in constraints))
for line in _in[25:])
def pt2(_in):
constraints = [[range(int((b := a.split("-"))[0]), int(b[1])+1)
for a in line.split(": ")[1].split(" or ")]
for line in _in[:20]]
# all(any(any())) => ALL numbers on a ticket match ANY constraint in ANY constraint group
tickets = [[int(n) for n in line.strip().split(",")]
for line in _in[25:]
if all(any(any(int(n) in cons
for cons in constraint)
for constraint in constraints)
for n in line.strip().split(","))]
# for each field
# assume it can be anything
candidates = [set(range(20)) for _ in range(20)] # one set per field
for ticket in tickets:
for f, field in enumerate(ticket):
for c, constraint in enumerate(constraints):
if c in candidates[f] and not any(field in cons for cons in constraint):
candidates[f].remove(c)
know = [-1 for _ in range(20)]
while any(len(c) > 0 for c in candidates):
for c, cand in enumerate(candidates):
if len(cand) == 1:
know[c] = cand.pop()
to_remove = know[c]
break
for cand in candidates:
if to_remove in cand:
cand.remove(to_remove)
my = list(int(n) for n in _in[22].strip().split(","))
res = 1
for f, field in enumerate(know):
if field < 6:
res *= my[f]
return res
if __name__ == "__main__":
input = aoc20.read_input(sys.argv[1:], 16)
print(pt1(input))
print(pt2(input))
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