Update README.md

Author: yanglr

README.md

@@ -1,3 +1,10 @@
-# Leetcode-CSharp
+# Leetcode in C#
 C#刷遍Leetcode系列
 Leetcode solutions written in CSharp.
+
+## 重要通知
+
+C#版的leetcode题解已全部移动到:
+<https://github.com/yanglr/leetcode-ac/tree/master/csharp-leetcode>
+
+欢迎 fork/star 新仓库 [leetcode-ac](https://github.com/yanglr/leetcode-ac) 😎