diff --git a/two-sum/DaleSeo-test.py b/two-sum/DaleSeo-test.py
new file mode 100644
index 0000000000..2d71c22e4f
--- /dev/null
+++ b/two-sum/DaleSeo-test.py
@@ -0,0 +1,10 @@
+# TC: O(n)
+# SC: O(n)
+class Solution:
+    def twoSum(self, nums: list[int], target: int) -> list[int]:
+        seen = {}
+        for i, num in enumerate(nums):
+            if target - num in seen:
+                return [seen[target - num], i]
+            seen[num] = i
+        return []
diff --git a/valid-parentheses/DaleSeo-test.py b/valid-parentheses/DaleSeo-test.py
new file mode 100644
index 0000000000..fb1e865229
--- /dev/null
+++ b/valid-parentheses/DaleSeo-test.py
@@ -0,0 +1,13 @@
+# TC: O(n)
+# SC: O(n)
+class Solution:
+    def isValid(self, s: str) -> bool:
+        pairs = {")": "(", "]": "[", "}": "{"}
+        stack = []
+        for ch in s:
+            if ch in pairs:
+                if not stack or stack.pop() != pairs[ch]:
+                    return False
+            else:
+                stack.append(ch)
+        return not stack