Create Valid Parentheses.py

Author: davijit868

Data Structures/Stack/Valid Parentheses.py

@@ -0,0 +1,30 @@
+'''
+
+Problem 20 | Valid Parentheses
+https://leetcode.com/problems/valid-parentheses/
+
+'''
+
+class Solution:
+ def isValid(self, s: str) -> bool:
+ stack = []
+ for i in s:
+ if i in "({[":
+ stack.append(i)
+ elif len(stack):
+ if stack[-1] == "(" and i == ")":
+ stack.pop(-1)
+ elif stack[-1] == "{" and i == "}":
+ stack.pop(-1)
+ elif stack[-1] == "[" and i == "]":
+ stack.pop(-1)
+ else:
+ return False
+ else:
+ return False
+ if len(stack):
+ return False
+ else:
+ return True
+ 
+