stackの問題：「20. Valid Parentheses」を解いてみる - Qiita

class Solution: def isValid(self, s: str) -> bool: if len(s)%2 != 0: return False dic = {'(':')','{':'}','[':']'} stack = list() for i, c in enumerate(s): if s[i] in dic: # verify only left-bracket stack.append(s[i]) # add only left-bracket else: if len(stack) != 0 and dic[stack[-1]] == s[i]: stack.pop() # remove a last element else: return False if len(stack) == 0: return True