Merge pull request go101#273 from yhliyr/fix-quizzes-slice-2-code

fix quizzes slice-2 code error

pages/quizzes/slice-2.html

@@ -99,7 +99,7 @@ <h1>slice 2</h1>
 	var x = []string{"A", "B", "C"}
 
 	for i, s := range x {
-		print(i, s, " ")
+		print(i, s, ",")
 		x = append(x, "Z")
 		x[i+1] = "Z"
 	}