1. Valid Palindrome

リストに変換

class Solution:
    def isPalindrome(self, s: str) -> bool:
        strs = []
        for char in s:
            if char.isalnum():
                strs.append(char.lower())
 		
        //펠린드롬 여부 판별
        while len(strs) > 1:
            if strs.pop(0) != strs.pop():
                return False
        
        return True
        

データ・ウェアハウスによる最適化

class Solution:
    def isPalindrome(self, s: str) -> bool:
        strs: Deque = collections.deque()
        
        for char in s:
        	if char.isalnum():
            	strs.append(char.lower())
        
        while len(strs) > 1:
        	if strs.popleft() != strs.pop():
            	return False
        
        return True

スライドの使用

class Solution:
    def isPalindrome(self, s: str) -> bool:
        s = s.lower()
        
        //정규식으로 불필요한 문자 필터링
        s= re.sub('[^a-z0-9]', '', s)
        return s ==  s[::-1] //슬라이싱 (뒤집기)

文字列のスライド