题解 | #括号序列#

class Solution:
    def isValid(self , s ):
        # write code here
        stack = []
        match = {'(':')', '[':']','{':'}'}
        for i in s:
            if i in match:
                stack.append(i)
            else: 
                if not stack or match[stack.pop()] != i:
                    return False
        return not stack