advent-of-code/2017-python/solutions/day_09.py

import re

from solutions import BaseSolution


class Solution(BaseSolution):
    input_file = "09.txt"

    def __str__(self):
        return "Day 9: Stream Processing"

    def solve(self, puzzle_input):
        level = 0
        groups = []
        stream = re.sub(r"!.", "", puzzle_input)
        stream = re.sub(r"<[^>]*>", "", stream)
        for c in stream:
            if c == "{":
                level += 1
            if c == "}":
                groups.append(level)
                level -= 1
        return sum(groups)

    def solve_again(self, puzzle_input):
        stream = re.sub(r"!.", "", puzzle_input)
        garbage = re.findall(r"<([^>]*)>", stream)
        return sum([len(g) for g in garbage])


if __name__ == "__main__":
    solution = Solution()
    solution.show_results()