aoc-2021/10_day/code.py

import fileinput

scores = [3, 57, 1197, 25137]

opening_chars = ['(', '[', '{', '<']
closing_chars = [')', ']', '}', '>']

lines = fileinput.input()

score = []
completions = []
completion_points = []

for line in lines:
	total = 0
	stack = []
	line = line.strip()
	complete = True
	for column, c in enumerate(line):
		if c in opening_chars:
			stack.append(opening_chars.index(c))
		if c in closing_chars:
			i = closing_chars.index(c)
			if stack[-1] != i:
				expected_i = opening_chars.index(stack[-1])
				# print(line)

				# print(''.join(column*[' ']+['^']))
				# print(f'Expected {closing_chars[expected_i]} but found {c}')
				# print('')
				score.append(scores[i])
				complete = False
				break
			stack.pop()
	if not complete: continue
	# the line is just incomplete
	completion = []
	while len(stack) > 0:
		i = opening_chars.index(stack.pop())
		char = closing_chars[i]
		total = total*5 + (i+1)
		completion.append(char)
	completion_points.append(total)
	print(''.join(completion))
completion_points.sort()

print('part 1')
print(score)
print(sum(score))

print('part 2')
print(completion_points)
print(completion_points[len(completion_points)//2])