81 lines
1.8 KiB
Python
Executable file
81 lines
1.8 KiB
Python
Executable file
#!/usr/bin/env python
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import dataclasses
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import enum
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import operator
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import sys
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from typing import Optional
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class Operator(str, enum.Enum):
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ADD = "+"
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SUB = "-"
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MUL = "*"
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DIV = "/"
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def __call__(self, lhs: int, rhs: int) -> int:
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OPERATIONS = {
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self.ADD: operator.add,
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self.SUB: operator.sub,
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self.MUL: operator.mul,
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self.DIV: operator.floordiv,
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}
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return OPERATIONS[self](lhs, rhs)
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class Monkey:
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def get_value(self, monkeys: dict[str, "Monkey"]) -> int:
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raise NotImplementedError
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@dataclasses.dataclass
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class YellerMonkey(Monkey):
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value: int
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def get_value(self, monkeys: dict[str, "Monkey"]) -> int:
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return self.value
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@dataclasses.dataclass
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class MathMonkey(Monkey):
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lhs: str
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op: Operator
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rhs: str
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_value: Optional[int] = dataclasses.field(default=None, init=False)
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def get_value(self, monkeys: dict[str, "Monkey"]) -> int:
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if self._value is None:
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self._value = self.op(
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monkeys[self.lhs].get_value(monkeys),
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monkeys[self.rhs].get_value(monkeys),
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)
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return self._value
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def solve(input: list[str]) -> int:
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def parse_monkey(input: str) -> tuple[str, Monkey]:
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name, value = input.split(": ")
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monkey: Monkey
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match value.split():
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case [lhs, op, rhs]:
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monkey = MathMonkey(lhs, Operator(op), rhs)
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case [n]:
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monkey = YellerMonkey(int(n))
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case _:
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assert False # Sanity check
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return name, monkey
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monkeys = dict(map(parse_monkey, input))
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return monkeys["root"].get_value(monkeys)
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def main() -> None:
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input = sys.stdin.read().splitlines()
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print(solve(input))
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if __name__ == "__main__":
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main()
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