import re


def part1(file):
    acc = []
    with open(file) as f:
        for line in f:
            digits = [match for match in re.findall(r"\d", line)]
            acc.append(int(f"{digits[0]}{digits[-1]}"))
    return sum(acc)


def part2(file):
    numbers = ["one", "two", "three", "four", "five", "six", "seven", "eight", "nine"]

    acc = []
    with open(file) as f:
        for line in f:
            line = re.sub(
                "|".join(f"(?=({number}))" for number in numbers),
                lambda match: str(
                    numbers.index([i for i in match.groups() if i is not None][0]) + 1
                ),
                line,
            )
            digits = [match for match in re.findall(r"\d", line)]
            acc.append(int(f"{digits[0]}{digits[-1]}"))
    return sum(acc)


if __name__ == "__main__":
    assert part1("example_part1.txt") == 142
    print(part1("input.txt"))

    assert part2("example_part2.txt") == 281
    print(part2("input.txt"))