코데풀유튜브(youtube.com/@codapul) 구독 부탁드립니다.

main.py

import copy

candidates: list[str] = []
max_length = 0

def solution(s:str):
    questionMarkIdxes = []
    for idx in range(len(s)):
        if s[idx] == '?':
            questionMarkIdxes.append(idx)

    replace_questionmark(s, questionMarkIdxes)

    for candi in candidates:
        indexes = [-1]

        while True:
            idx = candi.find('<>', indexes[-1] + 1)
            if idx == -1:
                break
            else:
                indexes.append(idx)

        indexes.pop(0)
        if len(indexes) > 0:
            palindrome_length(candi, indexes)

    return max_length

def replace_questionmark(s, questionMarkIdxes):
    if (len(questionMarkIdxes) == 0):
        candidates.append(s)
        return

    idx = questionMarkIdxes.pop(0)

    s1 = s[:idx] + '<' + s[idx + 1:]
    replace_questionmark(s1, copy.deepcopy(questionMarkIdxes))

    s2 = s[:idx] + '>' + s[idx + 1:]
    replace_questionmark(s2, copy.deepcopy(questionMarkIdxes))


def palindrome_length(s, indexes: list[int]):
    global max_length

    while len(indexes) > 0:
        idx = indexes.pop(0)
        ltidx = idx
        rtidx = idx +1
        my_length = 2

        ltidx = ltidx -1
        rtidx = rtidx +1

        while 0 <= ltidx and rtidx < len(s):
            if s[ltidx] == '<' and s[rtidx] == '>':
                my_length += 2
                ltidx = ltidx - 1
                rtidx = rtidx + 1
            else:
                break

        max_length = max(max_length, my_length)

test_main.py

from unittest import TestCase
from main import solution


class Test(TestCase):
    def test1_solution(self):
        self.assertEqual(4, solution('<><??>>'))

    def test2_solution(self):
        self.assertEqual(6, solution('??????'))

    def test3_solution(self):
        self.assertEqual(2, solution('<<?'))

    def test4_solution(self):
        self.assertEqual(0, solution('>?<'))