Add 0104-maximum-depth-of-binary-tree to topics.

Author: SHIMHUN

README.md

@@ -5,16 +5,20 @@
 | Problem Name | Difficulty |
 | ------- | ------- |
 | [0101-symmetric-tree](https://github.com/SHIMHUN/Algorithm/tree/main/LeetCode/Easy/0101-symmetric-tree/) | Easy |
+| [0104-maximum-depth-of-binary-tree](https://github.com/SHIMHUN/Algorithm/tree/main/LeetCode/Easy/0104-maximum-depth-of-binary-tree/) | Easy |
 ## Depth-First Search
 | Problem Name | Difficulty |
 | ------- | ------- |
 | [0101-symmetric-tree](https://github.com/SHIMHUN/Algorithm/tree/main/LeetCode/Easy/0101-symmetric-tree/) | Easy |
+| [0104-maximum-depth-of-binary-tree](https://github.com/SHIMHUN/Algorithm/tree/main/LeetCode/Easy/0104-maximum-depth-of-binary-tree/) | Easy |
 ## Breadth-First Search
 | Problem Name | Difficulty |
 | ------- | ------- |
 | [0101-symmetric-tree](https://github.com/SHIMHUN/Algorithm/tree/main/LeetCode/Easy/0101-symmetric-tree/) | Easy |
+| [0104-maximum-depth-of-binary-tree](https://github.com/SHIMHUN/Algorithm/tree/main/LeetCode/Easy/0104-maximum-depth-of-binary-tree/) | Easy |
 ## Binary Tree
 | Problem Name | Difficulty |
 | ------- | ------- |
 | [0101-symmetric-tree](https://github.com/SHIMHUN/Algorithm/tree/main/LeetCode/Easy/0101-symmetric-tree/) | Easy |
+| [0104-maximum-depth-of-binary-tree](https://github.com/SHIMHUN/Algorithm/tree/main/LeetCode/Easy/0104-maximum-depth-of-binary-tree/) | Easy |
 <!---LeetCode Topics End-->