423. Valid Parentheses
Description
Given a string containing just the characters ‘(‘, ‘)’, ‘{‘, ‘}’, ‘[’ and ‘]’, determine if the input string is valid.
Example
The brackets must close in the correct order, “()” and “()[]{}” are all valid but “(]” and “([)]” are not.
Code:
class Solution:
"""
@param s: A string
@return: whether the string is a valid parentheses
"""
def isValidParentheses(self, s):
# write your code here
dict = ['a']
if len(s)%2 != 0:
return False
var = {')':'(', ']':'[', '}':'{'}
for i in s:
if i in var :
if var[i]!=dict.pop():
return False
else:
dict.append(i)
if len(dict) != 1:
return False
else:
return True