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#!/usr/bin/env python3
import aoc20
import sys
def pt1(_in):
things = []
for line in _in[:20]:
thing = []
line = line.strip().split(": ")
for a in line[1].split(" or "):
b = a.split("-")
thing.append(range(int(b[0]), int(b[1])+1))
things.append(thing)
res = 0
for line in _in[25:]:
for n in line.strip().split(","):
n = int(n)
valid = False
for thing in things:
if any(n in r for r in thing):
valid = True
break
if not valid:
res += n
return res
def pt2(_in):
constraints = []
for line in _in[:20]:
thing = []
line = line.strip().split(": ")
for a in line[1].split(" or "):
b = a.split("-")
thing.append(range(int(b[0]), int(b[1])+1))
constraints.append(thing)
tickets = []
for line in _in[25:]:
valid_ticket = True
for n in line.strip().split(","):
n = int(n)
valid_field = False
for thing in constraints:
if any(n in r for r in thing):
valid_field = True
break
if not valid_field:
valid_ticket = False
break
if valid_ticket:
tickets.append(list(int(n) 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 t, ticket in enumerate(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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