update

Author: longshilin

README.md

@@ -78,4 +78,4 @@ CBTType root = null;			// 定义二叉树根结点引用
 
 - [单例模式的六种实现](./src/review02#top)
 - [二位数组中的查找](https://github.com/yilong0722/Data-structure-and-algorithm-Java/tree/master/src/review03#top)
-- [字符串替换空格](./src/review04#top) 
+- [字符串替换空格](https://github.com/yilong0722/Data-structure-and-algorithm-Java/tree/master/src/review04#top)