diff --git a/chapter01/01.1.md b/chapter01/01.1.md
index c7544cc..e45dc32 100644
--- a/chapter01/01.1.md
+++ b/chapter01/01.1.md
@@ -309,7 +309,7 @@ type Seeker interface {
 
 ```go
 reader := strings.NewReader("Go语言中文网")
-reader.Seek(-6, io.SEEK_END)
+reader.Seek(-6, io.SeekEnd)
 r, _, _ := reader.ReadRune()
 fmt.Printf("%c\n", r)
 ```