diff --git a/src/my_project/interviews/top_150_questions_round_22/ex_65_lru_cache.py b/src/my_project/interviews/top_150_questions_round_22/ex_65_lru_cache.py
new file mode 100644
index 00000000..22b4f7ed
--- /dev/null
+++ b/src/my_project/interviews/top_150_questions_round_22/ex_65_lru_cache.py
@@ -0,0 +1,26 @@
+from typing import List, Union, Collection, Mapping, Optional
+from abc import ABC, abstractmethod
+from collections import OrderedDict
+
+class LRUCache:
+
+    def __init__(self, capacity: int):
+        self.capacity = capacity 
+        self.dic = OrderedDict()
+
+
+    def get(self, key: int) -> int:
+
+        if key not in self.dic:
+            return -1
+        val = self.dic[key]
+        self.dic.move_to_end(key)
+        return val 
+
+    def put(self, key: int, value: int) -> None:
+        
+        self.dic[key] = value  
+        self.dic.move_to_end(key)
+
+        if len(self.dic) > self.capacity:
+            self.dic.popitem(last=False)
\ No newline at end of file
diff --git a/src/my_project/interviews/top_150_questions_round_22/ex_66_maximum_depth_binary_tree.py b/src/my_project/interviews/top_150_questions_round_22/ex_66_maximum_depth_binary_tree.py
new file mode 100644
index 00000000..a41e6978
--- /dev/null
+++ b/src/my_project/interviews/top_150_questions_round_22/ex_66_maximum_depth_binary_tree.py
@@ -0,0 +1,17 @@
+from typing import List, Union, Collection, Mapping, Optional
+from abc import ABC, abstractmethod
+
+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 not root:
+            return 0
+        else: 
+            return max(self.maxDepth(root.left), self.maxDepth(root.right)) + 1       
\ No newline at end of file
diff --git a/src/my_project/interviews_typescript/top_150_questions_round_1/TreeNode.ts b/src/my_project/interviews_typescript/top_150_questions_round_1/TreeNode.ts
new file mode 100644
index 00000000..df3eb8a6
--- /dev/null
+++ b/src/my_project/interviews_typescript/top_150_questions_round_1/TreeNode.ts
@@ -0,0 +1,11 @@
+export class TreeNode {
+    val: number;
+    left: TreeNode | null;
+    right: TreeNode | null;
+
+    constructor(val: number = 0, left: TreeNode | null = null, right: TreeNode | null = null) {
+        this.val = val;
+        this.left = left;
+        this.right = right;
+    }
+}
\ No newline at end of file
diff --git a/src/my_project/interviews_typescript/top_150_questions_round_1/ex_65_lru_cache.ts b/src/my_project/interviews_typescript/top_150_questions_round_1/ex_65_lru_cache.ts
new file mode 100644
index 00000000..417c2c91
--- /dev/null
+++ b/src/my_project/interviews_typescript/top_150_questions_round_1/ex_65_lru_cache.ts
@@ -0,0 +1,34 @@
+class LRUCache {
+    private capacity: number;
+    private cache: Map<number, number>;
+
+    constructor(capacity: number) {
+        this.capacity = capacity;
+        this.cache = new Map<number, number>();
+    }
+
+    get(key: number): number {
+        if (!this.cache.has(key)) {
+            return -1;
+        }
+        const value = this.cache.get(key)!;
+        // Move to end (most recently used)
+        this.cache.delete(key);
+        this.cache.set(key, value);
+        return value;
+    }
+
+    put(key: number, value: number): void {
+        // If key exists, delete it first to update position
+        if (this.cache.has(key)) {
+            this.cache.delete(key);
+        }
+        this.cache.set(key, value);
+        
+        // If capacity exceeded, remove the least recently used (first item)
+        if (this.cache.size > this.capacity) {
+            const firstKey = this.cache.keys().next().value!;
+            this.cache.delete(firstKey);
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/my_project/interviews_typescript/top_150_questions_round_1/ex_66_maximum_depth_binary_tree.ts b/src/my_project/interviews_typescript/top_150_questions_round_1/ex_66_maximum_depth_binary_tree.ts
new file mode 100644
index 00000000..f9898575
--- /dev/null
+++ b/src/my_project/interviews_typescript/top_150_questions_round_1/ex_66_maximum_depth_binary_tree.ts
@@ -0,0 +1,10 @@
+import { TreeNode } from './TreeNode';
+
+function maxDepth(root: TreeNode | null): number {
+    if (!root) {
+        return 0;
+    } else {
+        return Math.max(maxDepth(root.left), maxDepth(root.right)) + 1;
+    }
+}
+
diff --git a/tests/test_150_questions_round_22/test_65_lru_cache_round_22.py b/tests/test_150_questions_round_22/test_65_lru_cache_round_22.py
new file mode 100644
index 00000000..56f15cba
--- /dev/null
+++ b/tests/test_150_questions_round_22/test_65_lru_cache_round_22.py
@@ -0,0 +1,22 @@
+import unittest
+from src.my_project.interviews.top_150_questions_round_22\
+.ex_65_lru_cache import LRUCache
+
+class LRUCacheTestCase(unittest.TestCase):
+
+    def test_example_1(self):
+        # Example 1:
+        # Input: ["LRUCache", "put", "put", "get", "put", "get", "put", "get", "get", "get"]
+        #        [[2], [1, 1], [2, 2], [1], [3, 3], [2], [4, 4], [1], [3], [4]]
+        # Output: [null, null, null, 1, null, -1, null, -1, 3, 4]
+        
+        lRUCache = LRUCache(2)
+        self.assertIsNone(lRUCache.put(1, 1))  # cache is {1=1}
+        self.assertIsNone(lRUCache.put(2, 2))  # cache is {1=1, 2=2}
+        self.assertEqual(lRUCache.get(1), 1)    # return 1
+        self.assertIsNone(lRUCache.put(3, 3))  # LRU key was 2, evicts key 2, cache is {1=1, 3=3}
+        self.assertEqual(lRUCache.get(2), -1)   # returns -1 (not found)
+        self.assertIsNone(lRUCache.put(4, 4))  # LRU key was 1, evicts key 1, cache is {4=4, 3=3}
+        self.assertEqual(lRUCache.get(1), -1)   # return -1 (not found)
+        self.assertEqual(lRUCache.get(3), 3)    # return 3
+        self.assertEqual(lRUCache.get(4), 4)    # return 4
\ No newline at end of file
diff --git a/tests/test_150_questions_round_22/test_66_maximum_depth_binary_tree_round_22.py b/tests/test_150_questions_round_22/test_66_maximum_depth_binary_tree_round_22.py
new file mode 100644
index 00000000..dd48c4a4
--- /dev/null
+++ b/tests/test_150_questions_round_22/test_66_maximum_depth_binary_tree_round_22.py
@@ -0,0 +1,50 @@
+import unittest
+from src.my_project.interviews.top_150_questions_round_22\
+.ex_66_maximum_depth_binary_tree import Solution, TreeNode
+
+class MaximumDepthBinaryTreeTestCase(unittest.TestCase):
+
+    def create_binary_tree(self, values):
+        """
+        Helper function to create a binary tree from a list of values (level-order).
+        
+        :param values: List of node values (None represents null nodes)
+        :return: Root of the binary tree
+        """
+        if not values:
+            return None
+        
+        root = TreeNode(values[0])
+        queue = [root]
+        i = 1
+        
+        while queue and i < len(values):
+            node = queue.pop(0)
+            
+            if i < len(values) and values[i] is not None:
+                node.left = TreeNode(values[i])
+                queue.append(node.left)
+            i += 1
+            
+            if i < len(values) and values[i] is not None:
+                node.right = TreeNode(values[i])
+                queue.append(node.right)
+            i += 1
+        
+        return root
+
+    def test_example_1(self):
+        # Example 1: Input: root = [3,9,20,null,null,15,7]
+        # Output: 3
+        solution = Solution()
+        root = self.create_binary_tree([3, 9, 20, None, None, 15, 7])
+        result = solution.maxDepth(root)
+        self.assertEqual(result, 3)
+
+    def test_example_2(self):
+        # Example 2: Input: root = [1,null,2]
+        # Output: 2
+        solution = Solution()
+        root = self.create_binary_tree([1, None, 2])
+        result = solution.maxDepth(root)
+        self.assertEqual(result, 2)
\ No newline at end of file