A solution for: https://programmers.co.kr/learn/courses/30/lessons/42579?language=python3

best_album.py

from collections import Counter, defaultdict


def solution(genres, plays):
    song_limit = 2
    answer = []

    songs = defaultdict(dict)
    _genre_counter_dict = defaultdict(int)

    for i, (genre, play_cnt) in enumerate(zip(genres, plays)):
        _genre_counter_dict[genre] += play_cnt
        songs[genre][i] = play_cnt
    genre_counter = Counter(_genre_counter_dict)

    for genre, _ in genre_counter.most_common():
        for i, __ in Counter(songs[genre]).most_common(song_limit):
            answer.append(i)

    return answer


if __name__ == '__main__':
    args = ["classic", "pop", "classic", "classic", "pop"], [500, 600, 150, 800, 2500]
    print(solution(*args))