adding valid parentheses

Author: daiyongg-kim

valid-parentheses/daiyongg-kim.py

@@ -0,0 +1,22 @@
+class Solution:
+    def isValid(self, s: str) -> bool:
+        stack = []
+
+        for c in s:
+            if c == '(' or c == '[' or c == '{':
+                stack.append(c)
+            else:
+                if not stack:
+                    return False
+                
+                cur = stack.pop()
+                if cur == '(' and c != ')':
+                    return False
+                if cur == '{' and c != '}':
+                    return False
+                if cur == '[' and c != ']':
+                    return False
+        if not stack:
+            return True
+        else:
+            return False