Update SinglyLinkedListTest.java

src/test/java/com/nbee/solution/practice/SinglyLinkedListTest.java

@@ -12,4 +12,14 @@ public class SinglyLinkedListTest {
         list.addFirst(6);
         list.loop0(i -> System.out.println(i + " "));
     }
+    @Test
+    public void singlyLinkedListIteratorTest(){
+        list.addFirst(1);
+        list.addFirst(3);
+        list.addFirst(5);
+        list.addFirst(6);
+        for (Integer value: list) {
+            System.out.println(value);
+        }
+    }
 }