aoc-2020/6.py

lines = []

with open("6.input") as f:
    for line in f.readlines():
        lines.append(line.strip())

yesanswers = set()
yes_count = 0

for line in lines:
    if line == "":
        yes_count += len(yesanswers)
        yesanswers = set()
    else:
        yesanswers = yesanswers.union(set(line))

yes_count += len(yesanswers)

print("Answer 1: {}".format(yes_count))

yes_count = 0
yesanswers = None

for line in lines:
    if line == "":
        yes_count += len(yesanswers)
        yesanswers = None
    else:
        if yesanswers is None:
            yesanswers = set(line)
        else:
            yesanswers = yesanswers.intersection(set(line))

yes_count += len(yesanswers)

print("Answer 2: {}".format(yes_count))