有效的括号

实现思路

• 设立判定条件
• 遍历的范围

代码实现

class Solution(object):
    def isValid(self, s):
        """
        :type s: str
        :rtype: bool
        """
        n=len(s)
        for i in range(0,n-1):
            if s[i]=='(' and s[i+1]!=')':
                return False
            if s[i]=='[' and s[i+1]!=']':
                return False
            if s[i]=='{' and s[i+1]!='}':
                return False
        return True