【Leetcode-python】栈和队列题I
class Solution(object):
"""
定义一个栈和一个字典
如果进入左括号则append
如果进入右括号则查看栈顶是否为空，非空与栈顶元素比较，两者匹配则继续，不匹配则返回错误
"""
def isValid(self,s):
stack = []
map = {')':'(',']':'[','}':'{'}
for x in s:
if x not in map:
stack.append(x)
elif not stack or map[x]!=stack.pop():
return False
return not stack