diff --git a/maximum-depth-of-binary-tree/mandel-17.py b/maximum-depth-of-binary-tree/mandel-17.py
new file mode 100644
index 0000000000..a15a029561
--- /dev/null
+++ b/maximum-depth-of-binary-tree/mandel-17.py
@@ -0,0 +1,26 @@
+import collections
+from typing import Optional
+
+class TreeNode:
+    def __init__(self, val=0, left=None, right=None):
+        self.val = val
+        self.left = left
+        self.right = right
+
+class Solution:
+    def maxDepth(self, root: Optional[TreeNode]) -> int:
+        if root is None:
+            return 0
+        queue = collections.deque([root])
+        depth = 0
+
+        while queue:
+            depth += 1
+            for _ in range(len(queue)):
+                current_root = queue.popleft()
+                if current_root.left:
+                    queue.append(current_root.left)
+                if current_root.right:
+                    queue.append(current_root.right)
+        return depth
+    
diff --git a/merge-two-sorted-lists/mandel-17.py b/merge-two-sorted-lists/mandel-17.py
new file mode 100644
index 0000000000..828864ad45
--- /dev/null
+++ b/merge-two-sorted-lists/mandel-17.py
@@ -0,0 +1,16 @@
+from typing import Optional
+
+class ListNode:
+    def __init__(self, val=0, next=None):
+        self.val = val
+        self.next = next
+
+class Solution:
+    def mergeTwoLists(self, list1: Optional[ListNode], list2: Optional[ListNode]) -> Optional[ListNode]:
+        if (not list1) or (list2 and list1.val > list2.val):
+            list1, list2 = list2, list1
+        if list1:
+            list1.next = self.mergeTwoLists(list1.next, list2)
+        
+        return list1
+