[Programmers] 코딩테스트 입문 #2 (with Python)

목차

 

특이한 정렬

https://school.programmers.co.kr/learn/courses/30/lessons/120880/questions

프로그래머스

from collections import defaultdict

def solution(numlist, n):
    index_lst = [abs(n - e) for e in numlist]

    inverse = [(idx, value) for idx, value in enumerate(index_lst)]

    offset_group = {}  # 같은 offset 위치를 같은 그룹으로 묶기

    for index, value in sorted(inverse, key=lambda x: x[1]):

        if value not in offset_group:
            offset_group[value] = [index]
        else:
            offset_group[value].append(index)

    answer = []
    for _, index in offset_group.items():

        index = sorted([numlist[i] for i in index])
        for e in sorted(index, reverse=True):
            answer.append(e)

    return answer

 

 

중복된 문자 제거

https://school.programmers.co.kr/learn/courses/30/lessons/120888

def solution(my_string):

    hmap = {}

    for ch in my_string:
        if ch not in hmap:
            hmap[ch] = 0

    return ''.join(hmap.keys())

문자열 카운트를 활용하는것도 좋은 방법같다.

def solution(my_string):
    answer = []
    for i in my_string :
        if answer.count(i) == 0 :
            answer.append(i)
    return ''.join(answer)