https://programmers.co.kr/learn/courses/30/lessons/42890?language=python3 코딩테스트 연습 - 후보키 [["100","ryan","music","2"],["200","apeach","math","2"],["300","tube","computer","3"],["400","con","computer","4"],["500","muzi","music","3"],["600","apeach","music","2"]] 2 programmers.co.kr 최종 코드 GitHub -> https://github.com/hwayeon351/Programmers-Algorithms/blob/main/level2_후보키.py GitHub - hwayeon351/Prog..