题解 | #有效括号序列#

#
# 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
#
# 
# @param s string字符串 
# @return bool布尔型
#
class Solution:
    def isValid(self , s: str) -> bool:
        if len(s)%2 != 0:
            return False # 长度不是2的倍数肯定不行
        stack = []
        for char in s:
            try:
                if char == ')':
                    if stack[-1] == '(':
                        stack.pop()
                    else:
                        return False
                elif char == ']':
                    if stack[-1] == '[':
                        stack.pop()
                    else:
                        return False
                elif char == '}':
                    if stack[-1] == '{':
                        stack.pop()
                    else:
                        return False
                else:
                    stack.append(char)
            except:
                return False
        return len(stack)==0