diff --git a/leetcode/README.md b/leetcode/README.md
index 08e6a096..214c1832 100644
--- a/leetcode/README.md
+++ b/leetcode/README.md
@@ -51,6 +51,7 @@ LeetCode
 |520|[Detect Capital](https://leetcode.com/problems/detect-capital/) | [C](./src/520.c)|Easy|
 |561|[Array Partition I](https://leetcode.com/problems/array-partition-i/) | [C](./src/561.c)|Easy|
 |617|[Merge Two Binary Trees](https://leetcode.com/problems/merge-two-binary-trees/) | [C](./src/617.c)|Easy|
+|647|[Palindromic Substring](https://leetcode.com/problems/palindromic-substrings/) | [C](./src/647.c)|Medium|
 |674|[Longest Continuous Increasing Subsequence](https://leetcode.com/problems/longest-continuous-increasing-subsequence/) | [C](./src/674.c)|Easy|
 |700|[Search in a Binary Search Tree](https://leetcode.com/problems/search-in-a-binary-search-tree/) | [C](./src/700.c)|Easy|
 |701|[Insert into a Binary Search Tree](https://leetcode.com/problems/insert-into-a-binary-search-tree/) | [C](./src/701.c)|Medium|