Update 04.2.md

en/04.2.md

@@ -96,7 +96,7 @@ If we want to know whether the user is male or female, we may use a radio button
 ```
 And we use the following code to validate the input:
 ```Go
-	slice:=[]int{1,2}
+	slice:=[]string{"1","2"}
 
 	for _, v := range slice {
     	if v == r.Form.Get("gender") {