advent-of-code/2022/03/python/main.py
2022-12-04 11:10:33 +01:00

83 lines
1.8 KiB
Python

#!/usr/bin/env python
from os.path import dirname, join
# Day 03
# Common
def read_input(filename):
data = join(dirname(__file__), '..', filename)
with open(data) as f:
return f.read().strip()
test = read_input('test.txt')
data = read_input('input.txt')
def score(char: str) -> int:
offset = 97-1 if char.islower() else 65-27
return ord(char) - offset
class Rucksack:
def __init__(self, items: str):
self.l = len(items) // 2
self.items = items
def find_common(self) -> str:
front = self.items[:self.l]
back = self.items[self.l:]
intersection = set(front).intersection(set(back))
return list(intersection)[0]
class Supplies:
def __init__(self, rucksacks: list[Rucksack]) -> None:
self.rucksacks = rucksacks
def get_common(self):
return sum([
score(rucksack.find_common())
for rucksack in self.rucksacks
])
def groups(self):
group_size = 3
total = 0
for i in range(len(self.rucksacks)//group_size):
i *= group_size
subset = self.rucksacks[i:i+group_size]
sets = [set(rucksack.items) for rucksack in subset]
chars = sets[0]
for s in sets[1:]:
chars = chars.intersection(s)
total += score(list(chars)[0])
return total
@staticmethod
def parse(data: str):
rucksacks = [
Rucksack(item)
for item in data.split('\n')
]
return Supplies(rucksacks)
# 1
print('1.')
supplies = Supplies.parse(test)
print(supplies.get_common())
supplies = Supplies.parse(data)
print(supplies.get_common())
# 2
print('\n2.')
supplies = Supplies.parse(test)
print(supplies.groups())
supplies = Supplies.parse(data)
print(supplies.groups())