Advent of Code 2021: Day 6
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Refer to the previous post about AoC, and to the git repository with my solutions in Python 3.
Link to Day #6 puzzle.
Simulate lanternfish population growth using a counter to track fish by their internal timer.
python
#!/usr/bin/env python3
from collections import Counter
import sys
with open(sys.argv[1]) as input:
numbers = list(map(int, input.read().split(',')))
def simulation(days):
fish = Counter(numbers)
for _ in range(days):
next_fish = Counter()
for timer, count in fish.items():
if timer == 0:
next_fish[8] += fish[timer]
next_fish[6] += fish[timer]
else:
next_fish[timer - 1] += fish[timer]
fish = next_fish
print(sum(fish.values()))
simulation(80)
simulation(256)