This commit is contained in:
2021-12-10 11:56:59 +01:00
parent d1e4a2bb26
commit 8e135d06ac

View File

@@ -1,16 +1,14 @@
import sys
from typing import Optional
class InvalidChar(Exception):
pass
PAIRS = {
")": "(",
"]": "[",
"}": "{",
">": "<",
}
OPEN = ["(", "[", "{", "<"]
CLOSE = [")", "]", "}", ">"]
CLOSING_FOR_OPEN = dict(zip(CLOSE, OPEN))
SCORE_ONE = {
")": 3,
@@ -29,47 +27,51 @@ SCORE_TWO = {
def part_one(lines: list[str]) -> int:
score = 0
for line in lines:
try:
stack = []
for char in list(line):
# Open backets
if char in PAIRS.values():
stack.append(char)
# Close brackets
elif char in PAIRS:
for char in list(line):
if char in CLOSING_FOR_OPEN.values(): # Open backets
stack.append(char)
elif char in CLOSING_FOR_OPEN: # Close brackets
top = stack.pop()
if top != PAIRS[char]:
if top != CLOSING_FOR_OPEN[char]:
score += SCORE_ONE[char]
raise InvalidChar
except InvalidChar:
pass
return score
def part_two(lines: list[str]) -> int:
scores = []
for line in lines:
score = 0
try:
stack = [None]
for char in list(line):
# Open backets
if char in PAIRS.values():
stack.append(char)
# Close brackets
elif char in PAIRS:
try:
stack: list[Optional[str]] = [None]
for char in list(line):
if char in CLOSING_FOR_OPEN.values(): # Open backets
stack.append(char)
elif char in CLOSING_FOR_OPEN: # Close brackets
top = stack.pop()
if top != PAIRS[char]:
if top != CLOSING_FOR_OPEN[char]:
# Ignore invalid lines
raise InvalidChar
# Check not closed brackets
# Close unclosed pairs
while top := stack.pop():
score = score * 5 + SCORE_TWO[top]
scores.append(score)
except InvalidChar:
pass
@@ -79,6 +81,8 @@ def part_two(lines: list[str]) -> int:
if __name__ == "__main__":
import sys
lines = sys.stdin.readlines()
print("Part one:", part_one(lines))