Day 7 - Advent of Code 2016

""" day_07_01.py """

# usage: python3 day_07_01.py < input


def abba(text):
    """ check for abba pattern """
    return text[0] == text[3] and text[1] == text[2] and text[0] != text[1]


def tls(text):
    """ does text support tls per puzzle description """
    legit = False
    hypernet = False
    for i, char in enumerate(text):
        if char == '[':
            hypernet = True
            continue
        if char == ']':
            hypernet = False
            continue
        chunk = text[i:i + 4]
        if '[' in chunk:
            continue
        if ']' in chunk:
            continue
        if len(chunk) < 4:
            break
        if abba(chunk):
            if hypernet:
                return False
            legit = True
    return legit


count = 0
while True:
    try:
        ip = input()
    except EOFError:
        break
    if tls(ip):
        count += 1

print(count)

""" day_07_02.py """

# usage: python3 day_07_02.py < input


def aba(text):
    """ check for aba pattern """
    return text[0] == text[2] and text[0] != text[1]


def bab(text):
    """ calculate bab from aba """
    return text[1] + text[0] + text[1]


def ssl(text):
    """ does text support ssl per puzzle description """
    inner = set()
    outer = set()
    hypernet = False
    for i, char in enumerate(text):
        if char == '[':
            hypernet = True
            continue
        if char == ']':
            hypernet = False
            continue
        chunk = text[i:i + 3]
        if '[' in chunk:
            continue
        if ']' in chunk:
            continue
        if len(chunk) < 3:
            break
        if aba(chunk):
            if hypernet:
                inner.add(chunk)
            else:
                outer.add(chunk)

    for chunk in inner:
        if bab(chunk) in outer:
            return True
    return False


count = 0
while True:
    try:
        ip = input()
    except EOFError:
        break
    if ssl(ip):
        count += 1

print(count)