diff --git a/README.md b/README.md
index be361cd..68e550a 100644
--- a/README.md
+++ b/README.md
@@ -135,10 +135,10 @@ eval @inspect(sixSoles())
 
 ### DiffList
 
-[ [Goto The Playground](https://inet.xieyuheng.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) ]
+[ [Goto The Playground](https://inet.xieyuheng.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) ]
 
 ```inet
-import { List } from "https://code-of-inet-js.xieyuheng.com/std/datatype/List.i"
+import { List } from "https://code-of-inet-js.xieyuheng.com/docs/std/datatype/List.i"
 
 // Concatenation of lists is performed in linear time
 // with respect to its first argument.
@@ -185,7 +185,7 @@ rule diffOpen(target!, newBack, oldBack)
 
 // TEST
 
-import { cons } from "https://code-of-inet-js.xieyuheng.com/std/datatype/List.i"
+import { cons } from "https://code-of-inet-js.xieyuheng.com/docs/std/datatype/List.i"
 
 type Trivial