LeetCode-20: Valid Parentheses

LeetCode/easy/is_valid_20.py

@@ -0,0 +1,17 @@
+class Solution:
+    def isValid(self, s: str) -> bool:
+        p_map = {")": "(", "}": "{", "]": "["}
+        stack = []
+
+        for i in s:
+            if i in p_map:
+                if not stack:
+                    return False
+                elif stack[-1] == p_map[i]:
+                    stack.pop()
+                else:
+                    return False
+            else:
+                stack.append(i)
+
+        return len(stack) == 0

tests/test_leetcode.py

@@ -269,14 +269,18 @@ def test_reverse_integer(x: int, expected: int):
         (")", False),  # Single closing parenthesis
         ("(((((((((())))))))))", True),  # Deeply nested
         ("(((((((((()))", False),  # Deeply nested but incomplete
+        (")(", False),
     ],
 )
 def test_is_valid_parentheses(s: str, expected: bool):
+    from LeetCode.easy.is_valid_20 import Solution as Sol
     from LeetCode.valid_parentheses_20 import Solution
 
     solution = Solution()
     result = solution.isValid(s)
+    res = Sol().isValid(s)
     assert result == expected
+    assert res == expected, f'expected {expected} but got {res} for "{s}"'
 
 
 @pytest.mark.parametrize(