프로그래머스 42577. 전화번호 목록

https://school.programmers.co.kr/learn/courses/30/lessons/42577

프로그래머스

[해시 정석 풀이]

def solution(phone_book):
    answer = True
    hash_map = {}
    for phone_number in phone_book:
        hash_map[phone_number] = 1
    for phone_number in phone_book:
        temp = ""
        for number in phone_number:
            temp += number
            if temp in hash_map and temp != phone_number:
                answer = False
    return answer

[정렬 풀이]

def solution(phone_book):
    # 정렬 후 인접한 두 전화번호만 비교
    phone_book.sort()
    for i in range(len(phone_book) - 1):
        # phone_book[i+1]이 phone_book[i]로 시작하는지 확인
        if phone_book[i+1].startswith(phone_book[i]):
            return False
    return True