11/1 3진법 뒤집기
https://school.programmers.co.kr/learn/courses/30/lessons/68935
https://school.programmers.co.kr/learn/courses/30/lessons/68935
https://school.programmers.co.kr/learn/courses/30/lessons/64061
https://school.programmers.co.kr/learn/courses/30/lessons/42889
프로그래머스 실패율 문제에서, 람다를 이용해 딕셔너리를 정렬하는 코드가 나왔었다. .
https://school.programmers.co.kr/learn/courses/30/lessons/181926