#!/usr/bin/env python

import re
import argparse


RE_ABA = re.compile(r'(?=((\w)(?!\2)\w\2))')
RE_HYPERNET = re.compile(r'\[([^\]]+)\]')

def load_file(filename):
    with open(filename) as f:
        for line in f:
            yield line.strip()

def check_ip(data):
    def reverse_aba(aba):
        return "{}{}{}".format(aba[1], aba[0], aba[1])

    aba_all = []
    for aba in RE_ABA.findall(data):
        aba_all.append(aba[0])

    aba_hyper = []
    for hyper in RE_HYPERNET.findall(data):
        for aba in RE_ABA.findall(hyper):
            aba_hyper.append(aba[0])

    for aba in aba_hyper:
        aba_all.remove(aba)

    for aba in aba_hyper:
        if reverse_aba(aba) in aba_all:
            return 1
    return 0

def main(args):
    count = 0
    for LINE in load_file(args.input):
        count += check_ip(LINE)

    print(count)

if __name__ == "__main__":
    parser = argparse.ArgumentParser(description='AdventOfCode 2016 Day 01')
    parser.add_argument('--input', '-i', action='store',  required=True, help='input file')
    args = parser.parse_args()

    main(args)