solves lowest common ancestor of binary tree

Author: anishLearnsToCode

README.md

@@ -190,7 +190,7 @@
 | 232  | [Implement Queue Using Stacks](https://leetcode.com/problems/implement-queue-using-stacks)                                                                |                                 [![Java](assets/java.png)](src/MyQueue.java) [![Python](assets/python.png)](python/implement_queue_using_stacks.py)                                  |                                                                                                                                   |
 | 234  | [Palindrome Linked Lists](https://leetcode.com/problems/palindrome-linked-list)                                                                           |                              [![Java](assets/java.png)](src/PalindromeLinkedList.java) [![Python](assets/python.png)](python/palindrome_linked_list.py)                              |                                                                                                                                   |
 | 235  | [Lowest Common Ancestor of a Binary Search Tree](https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-search-tree)                            |                 [![Java](assets/java.png)](src/LowestCommonAncestorOfBinarySearchTree.java) [![Python](assets/python.png)](python/lowest_common_ancestor_of_bst.py)                  |                                                                                                                                   |
-| 236  | [Lowest Common Ancestor of a Binary Tree](https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree)                                          |                                                                                                                                                                                      |                                                                                                                                   |
+| 236  | [Lowest Common Ancestor of a Binary Tree](https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree)                                          |                                                        [![Java](assets/java.png)](src/LowestCommonAncestorOfBinaryTree.java)                                                         |                                                                                                                                   |
 | 237  | [Delete a Node In A Linked List](https://leetcode.com/problems/delete-node-in-a-linked-list)                                                              |                          [![Java](assets/java.png)](src/DeleteANodeInLinkedList.java) [![Python](assets/python.png)](python/delete_node_in_linked_list.py)                           |                                                                                                                                   |
 | 238  | [Product of Array Except Self](https://leetcode.com/problems/product-of-array-except-self)                                                                |                                                                                                                                                                                      |                                                                                                                                   |
 | 240  | [Search a 2D Matrix II](https://leetcode.com/problems/search-a-2d-matrix-ii)                                                                              |                                                                                                                                                                                      |                                                                                                                                   |

src/LowestCommonAncestorOfBinaryTree.java

@@ -0,0 +1,13 @@
+// https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree
+// T: O(N)
+// S: O(log(N))
+
+public class LowestCommonAncestorOfBinaryTree {
+    public TreeNode lowestCommonAncestor(TreeNode root, TreeNode p, TreeNode q) {
+        if (root == null || root == p || root == q) return root;
+        TreeNode left = lowestCommonAncestor(root.left, p, q);
+        TreeNode right = lowestCommonAncestor(root.right, p, q);
+        if (left != null && right != null) return root;
+        return left == null ? right : left;
+    }
+}