diff --git a/README.md b/README.md
index 155e265..4b3a660 100644
--- a/README.md
+++ b/README.md
@@ -169,6 +169,7 @@ My LeetCode solutions with Chinese explanation. 我的LeetCode中文题解。
 | 236 |[Lowest Common Ancestor of a Binary Tree](https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree/)|[C++](https://github.com/ShusenTang/LeetCode/blob/master/solutions/236.%20Lowest%20Common%20Ancestor%20of%20a%20Binary%20Tree.md)|Medium|  |
 | 237 |[Delete Node in a Linked List](https://leetcode.com/problems/delete-node-in-a-linked-list)|[C++](https://github.com/ShusenTang/LeetCode/blob/master/solutions/237.%20Delete%20Node%20in%20a%20Linked%20List.md)|Easy|  |
 | 238 |[Product of Array Except Self](https://leetcode.com/problems/product-of-array-except-self/)|[C++](https://github.com/ShusenTang/LeetCode/blob/master/solutions/238.%20Product%20of%20Array%20Except%20Self.md)|Medium|  |
+| 240 |[Search a 2D Matrix II](https://leetcode.com/problems/search-a-2d-matrix-ii/)|[C++](https://github.com/ShusenTang/LeetCode/blob/master/solutions/240.%20Search%20a%202D%20Matrix%20II.md)|Medium|  |
 | 242 |[Valid Anagram](https://leetcode.com/problems/valid-anagram)|[C++](https://github.com/ShusenTang/LeetCode/blob/master/solutions/242.%20Valid%20Anagram.md)|Easy|  |
 | 257 |[Binary Tree Paths](https://leetcode.com/problems/binary-tree-paths)|[C++](https://github.com/ShusenTang/LeetCode/blob/master/solutions/257.%20Binary%20Tree%20Paths.md)|Easy|  |
 | 258 |[Add Digits](https://leetcode.com/problems/add-digits)|[C++](https://github.com/ShusenTang/LeetCode/blob/master/solutions/258.%20Add%20Digits.md)|Easy|  |