clean the codes

Author: jameszhan

Diff for: README.md

@@ -3,8 +3,6 @@ LeetCode
 
 ### LeetCode Algorithm
 
-(Notes: "♥" means you need to buy a book from Leetcode)
-
 | # | Title | Solution | Difficulty |
 |---| ----- | -------- | ---------- |
 |1143|[Longest Common Subsequence](https://leetcode.com/problems/longest-common-subsequence/) | [Python](algorithms/1143-longest-common-subsequence.ipynb)|Medium|