AdventOfCode2022/05/day5.py
2022-12-11 02:26:42 +01:00

57 lines
2.3 KiB
Python

from re import fullmatch
from sys import argv, exit
re_instruction = r"move (\d+) from (\d+) to (\d+)\n"
MAX_CRATES = 8
STACK_COUNT = 9
def fill_stacks(cratestacks:list[str], lines:list[str]):
for _ in range(MAX_CRATES):
line = lines.pop(0).strip('\n')
if not '[' in line: return
for i in range(STACK_COUNT):
# if i * 4 + 1 > len(line):
# print(f"Error, i{i} len(line){len(line)}, line {line}")
if line[i*4] == '[': cratestacks[i] += line[i*4+1]
for i in range(len(cratestacks)):
cratestacks[i] = cratestacks[i][::-1]
def crate_mover_9000(cratestacks: list[str], amount:int, fromStack:int, toStack:int):
# print("9000", cratestacks, amount, fromStack, toStack)
for _ in range(amount):
cratestacks[toStack-1] += cratestacks[fromStack-1][-1]
cratestacks[fromStack-1] = cratestacks[fromStack-1][:-1]
def crate_mover_9001(cratestacks: list[str], amount:int, fromStack:int, toStack:int):
# print("9001", cratestacks, amount, fromStack, toStack, cratestacks[fromStack-1][(-amount):])
cratestacks[toStack-1] += cratestacks[fromStack-1][(-amount):]
cratestacks[fromStack-1] = cratestacks[fromStack-1][:(-amount)]
def main(filename):
with open(filename, 'r') as file:
lines = file.readlines()
cratestacks_1:list[str] = [ "" for _ in range(STACK_COUNT) ]
fill_stacks(cratestacks_1, lines)
cratestacks_2:list[str] = list(cratestacks_1)
for line in lines:
match = fullmatch(re_instruction, line)
if not match: continue
amount, fromStack, toStack = [ int(x) for x in match.groups() ]
# print(amount, fromStack, toStack)
crate_mover_9000(cratestacks_1, amount, fromStack, toStack);
crate_mover_9001(cratestacks_2, amount, fromStack, toStack);
top_crates_1 = ""
top_crates_2 = ""
for i in range(len(cratestacks_1)):
top_crates_1 += cratestacks_1[i][-1]
top_crates_2 += cratestacks_2[i][-1]
print(f"Using the CrateMover 9000, the crates at the top are: {top_crates_1}")
print(f"Using the CrateMover 9001, the crates at the top are: {top_crates_2}")
if __name__ == '__main__':
if not len(argv) == 2:
print(f"Expected exactly one argument (filename), got {len(argv)-1}")
exit(1)
main(argv[1])