[Python] 완주하지 못한 선수

 

풀이 1

def solution(participant, completion):
    participant.sort()
    completion.sort()
    
    for i in range(0, len(completion)):
        if participant[i] != completion[i]:
            return participant[i]
    return participant[-1]

 

풀이 2

import collections

def soltion(participant, completion):
    answer = collections.Counter(participant) - collections.Counter(completion)
    return list(answer.keys())[0]

 

collections.Counter(participant) # Counter({'leo': 1, 'kiki': 1, 'eden': 1})

list(answer.keys()) # ['leo']

list(answer.keys())[0] # 'leo'