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#!/usr/bin/env python3
import aoc20
import sys
import functools
class Node:
def __init__(self, name, children=[]):
self.name = name
self.children = children
self.parents = []
def __iter__(self):
yield from (child for child, _ in self.children)
def parse(_in):
nodes = {}
for line in _in:
line = line.split()
# muted lime bags contain 1 wavy lime bag, 1 vibrant green bag, 3 light yellow bags.
# 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
# dotted teal bags contain no other bags.
if line[4] != "no":
children = [(" ".join(line[i+1:i+3]), int(line[i+0])) for i in range(4, len(line), 4)]
else:
children = []
name = " ".join(line[0:2])
nodes[name] = Node(name, children)
for node in nodes.values():
node.children = [(nodes[node_str], amount) for node_str, amount in node.children]
for child in node:
child.parents.append(node)
return nodes
def pt1(_in):
@functools.cache
def types_above(node):
return node.parents + list(functools.reduce(lambda a, b: a + b, (types_above(parent) for parent in node.parents), []))
nodes = parse(_in)
return len(set(types_above(nodes["shiny gold"])))
def pt2(_in):
@functools.cache
def count_children(node):
return 1 + sum(child[1] * count_children(child[0]) for child in node.children)
nodes = parse(_in)
return count_children(nodes["shiny gold"]) - 1
if __name__ == "__main__":
input = aoc20.read_input(sys.argv[1:], 7)
# graph(parse(input))
print(pt1(input))
print(pt2(input))
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