#!/usr/bin/env python3


from typing import TextIO

ltrs = "abcdefghijklmnopqrstuvwxyz"
# lowercase: pos + 1
# uppercase: pos + 27


def find_common_char(one: str, two: str) -> str:
    for a in one:
        for b in two:
            if a == b:
                return a

    return ""


def find_common_char_three(one: str, two: str, three: str) -> str:
    for a in one:
        for b in two:
            for c in three:
                if a == b == c:
                    return a

    return ""


def get_priority(ltr: str) -> int:

    n = ltrs.find(ltr.lower())

    if ltr.isupper():
        return n + 27

    return n + 1


def part1(sacks: TextIO) -> int:

    sum: int = 0
    for sack in sacks:
        first = sack[: len(sack) // 2]
        second = sack[len(sack) // 2 :]

        sum += get_priority(find_common_char(first, second))

    return sum


def part2(sacks: TextIO) -> int:
    sum: int = 0

    line = sacks.readline().strip()

    while line != "":
        a, b, c = "", "", ""

        for i in range(0, 3):
            if line != "":  # lol
                a = line
                line = sacks.readline().strip()
                b = line
                line = sacks.readline().strip()
                c = line

                line = sacks.readline().strip()

                sum += get_priority((find_common_char_three(a, b, c)))

    return sum


if __name__ == "__main__":
    print(part1(open("day03.txt")))
    print(part2(open("day03.txt")))