AdventOfCode/2023/day8/p2.py

48 lines
1.0 KiB
Python

from math import gcd
import sys
steps, _, *rest = open(sys.argv[1]).read().splitlines()
network = {}
for line in rest:
pos, targets = line.split(" = ")
network[pos] = targets[1:-1].split(", ")
positions = [key for key in network if key.endswith("A")]
cycles = []
for current in positions:
cycle = []
current_steps = steps
step_count = 0
first_z = None
while True:
print(current_steps)
while step_count == 0 or not current.endswith("Z"):
step_count += 1
current = network[current][0 if current_steps[0] == "L" else 1]
print(current)
current_steps = current_steps[1:] + current_steps[0]
print(current_steps)
cycle.append(step_count)
if first_z is None:
first_z = current
step_count = 0
elif current == first_z:
break
cycles.append(cycle)
nums = [cycle[0] for cycle in cycles]
lcm = nums.pop()
for num in nums:
lcm = lcm * num // gcd(lcm, num)
print(lcm)