mirror of
https://github.com/cupcakearmy/advent-of-code.git
synced 2024-11-01 08:04:12 +01:00
87 lines
2.0 KiB
Python
87 lines
2.0 KiB
Python
#!/usr/bin/env python
|
|
|
|
import math
|
|
from collections import defaultdict
|
|
from os.path import dirname, join
|
|
|
|
# Day 14
|
|
|
|
# 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')
|
|
|
|
|
|
class Polymer:
|
|
def __init__(self, state: str, insertions: dict[str, str]):
|
|
self.state = state
|
|
self.insertions = insertions
|
|
self.states: defaultdict[str, int] = defaultdict(lambda: 0)
|
|
|
|
for i in range(len(self) - 1):
|
|
pair = self.state[i:i+2]
|
|
self.states[pair] += 1
|
|
|
|
def __len__(self):
|
|
return len(self.state)
|
|
|
|
def step(self):
|
|
new = defaultdict(lambda: 0)
|
|
for state, count in self.states.items():
|
|
if count == 0:
|
|
continue
|
|
insertion = self.insertions[state]
|
|
for key in [state[0] + insertion, insertion + state[1]]:
|
|
new[key] += count
|
|
self.states = new
|
|
|
|
def score(self):
|
|
elements = defaultdict(lambda: 0)
|
|
for state, count in self.states.items():
|
|
for element in state:
|
|
elements[element] += count
|
|
for element, count in elements.items():
|
|
elements[element] = math.ceil(elements[element]/2)
|
|
return max(elements.values()) - min(elements.values())
|
|
|
|
def flag(self, steps: int):
|
|
for _ in range(steps):
|
|
self.step()
|
|
print(self.score())
|
|
|
|
@staticmethod
|
|
def parse(data: str):
|
|
state, raw = data.split('\n\n')
|
|
lines = [
|
|
l.split(' -> ')
|
|
for l in raw.split('\n')
|
|
]
|
|
insertions = {
|
|
i[0]: i[1]
|
|
for i in lines
|
|
}
|
|
return Polymer(state.strip(), insertions)
|
|
|
|
|
|
# 1
|
|
print('1.')
|
|
|
|
polymer = Polymer.parse(test)
|
|
polymer.flag(10)
|
|
polymer = Polymer.parse(data)
|
|
polymer.flag(10)
|
|
|
|
# 2
|
|
print('\n2.')
|
|
polymer = Polymer.parse(test)
|
|
polymer.flag(40)
|
|
polymer = Polymer.parse(data)
|
|
polymer.flag(40)
|