import re

with open('input.text', 'r') as file:
    data: list[str] = file.readlines()


class Equation:
    result: int
    constants: list[int]

    def __init__(self, result: int, constants: list[int]):
        self.result = result
        self.constants = constants

    def is_valid_eq(self, eq: str) -> bool:
        tokens: list[str] = re.findall('\d+|\+|\*', eq)

        r = None
        add = True
        for token in tokens:
            if not r and token.isnumeric():
                r = int(token)
            elif token == '+':
                add = True
            elif token == '*':
                add = False
            elif add:
                r += int(token)
            elif not add:
                r *= int(token)

        return r == self.result
     
    def is_valid(self, s: str | None) -> bool:
        if s == None:
            s = ''
            for c in self.constants:
                s += (str(c) + ' ')
            return self.is_valid(s[:-1])
        elif ' ' in s:
            s1 = s.replace(' ', '+', 1)
            s2 = s.replace(' ', '*', 1)
            return self.is_valid(s1) or self.is_valid(s2)
        else:
            return self.is_valid_eq(s)


equations: list[Equation] = []

# Parse input
for line in data:
    if ':' in line:
        result, constants = line.split(':')
        result = int(result)
        constants = [int(n) for n in constants.strip().split(' ')]
        equations.append(Equation(result, constants))

# Part 1
total = 0
for equation in equations:
    if equation.is_valid(None):
        total += equation.result

print(f'Part 1: {total}')