[LeetCode/Python] Valid Parentheses

문제 설명

Given a string s containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.

An input string is valid if:

1. Open brackets must be closed by the same type of brackets.
2. Open brackets must be closed in the correct order.

 

예시

 

제한

• 1 <= s.length <= 104
• s consists of parentheses only '()[]{}'.

 

Valid Parentheses - LeetCode

 

풀이

class Solution:
    def isValid(self, s: str) -> bool:
        stack = []
        dict = {")":"(", "}":"{", "]":"["}
        for i in s:
            if i == "(" or i == "[" or i == "{":
                stack.append(i)
            elif i == ")" or i == "]" or i == "}":
                if len(stack) == 0:
                    return False
                if stack.pop() != dict[i]:
                    return False

        return len(stack) == 0