🌵20. Valid Parentheses
https://leetcode.com/problems/valid-parentheses/
js
/**
* @param {string} s
* @return {boolean}
*/
var isValid = function(s) {
var stack = []
var labels = {
'(': ')',
'[': ']',
'{': '}'
}
for (let ch of s) {
if (labels.hasOwnProperty(ch)) {
stack.push(ch)
} else if (stack.length === 0 || labels[stack.pop()] !== ch) {
return false
}
}
return stack.length === 0
}py
class Solution(object):
def isValid(self, s):
"""
:type s: str
:rtype: bool
"""
stack, labels = [], {'(': ')', '[': ']', '{': '}'}
for ch in s:
if ch in labels:
stack.append(ch)
elif len(stack) == 0 or labels[stack.pop()] != ch:
return False
return len(stack) == 0