Bruno BELANYI
1df896c32c
This is mostly about unused imports. A couple errors remain, but are fine in my book (using `l` as a variable name, assigning a lambda to a variable).
80 lines
1.5 KiB
Python
Executable file
80 lines
1.5 KiB
Python
Executable file
#!/usr/bin/env python
|
|
|
|
import sys
|
|
from typing import List
|
|
|
|
"""
|
|
E : T [ * T ]*
|
|
|
|
T : G [ + G ]*
|
|
|
|
G : '(' E ')' | CONSTANT
|
|
"""
|
|
|
|
|
|
def parse_g(expr: List[str]) -> int:
|
|
top = expr.pop(0)
|
|
if top == "(":
|
|
ans = parse_e(expr)
|
|
assert expr.pop(0) == ")"
|
|
return ans
|
|
return int(top)
|
|
|
|
|
|
def parse_t(expr: List[str]) -> int:
|
|
lhs = parse_g(expr)
|
|
while len(expr) and expr[0] == "+":
|
|
expr.pop(0)
|
|
rhs = parse_g(expr)
|
|
lhs += rhs
|
|
return lhs
|
|
|
|
|
|
def parse_e(expr: List[str]) -> int:
|
|
lhs = parse_t(expr)
|
|
while len(expr) and expr[0] == "*":
|
|
expr.pop(0)
|
|
rhs = parse_t(expr)
|
|
lhs *= rhs
|
|
return lhs
|
|
|
|
|
|
def parse_infix(input: List[str]) -> int:
|
|
"""
|
|
Parses the given string in infix notation.
|
|
"""
|
|
ans = parse_e(input)
|
|
assert len(input) == 0
|
|
return ans
|
|
|
|
|
|
def tokenize(expr: str) -> List[str]:
|
|
res = []
|
|
|
|
def split_tok(tok: str) -> None:
|
|
if "(" not in tok and ")" not in tok:
|
|
res.append(tok)
|
|
if "(" in tok:
|
|
res.append("(")
|
|
split_tok(tok[1:])
|
|
if ")" in tok:
|
|
split_tok(tok[:-1])
|
|
res.append(")")
|
|
|
|
for tok in expr.split():
|
|
split_tok(tok)
|
|
return res
|
|
|
|
|
|
def solve(raw: List[str]) -> int:
|
|
return sum(parse_infix(tokenize(expr)) for expr in raw)
|
|
|
|
|
|
def main() -> None:
|
|
input = [line.strip() for line in sys.stdin.readlines()]
|
|
print(solve(input))
|
|
|
|
|
|
if __name__ == "__main__":
|
|
main()
|