# Day 6 - Part 1
def marker_end_position(task):
    with open('input.dat') as f:
        data = f.read()
        distinct_characters = 0
        if task == "part1":
            distinct_characters = 4
        elif task == "part2":
            distinct_characters = 14
        for i in range(distinct_characters, len(data)):
            has_repeated_chars = len(set(data[i-distinct_characters:i])) != len(data[i-distinct_characters:i])
            if not has_repeated_chars:
                print(i)
                break


if __name__ == '__main__':
    marker_end_position("part2")