update,

it114105/itp3914/Assignment/21-22/List.java

@@ -0,0 +1,42 @@
+public class List {
+    private Node head;
+    private Node tail;
+    private int size;
+
+    public List(){
+        head = tail = null;
+        size = 0;
+    }
+
+    public boolean isEmply(){
+        return head == null;
+    }
+
+    public void append(Object data){
+        if(head == null){
+            head = tail = new Node(data);
+            size++;
+            return;
+        }
+
+        tail.next = new Node(data);
+        tail = tail.next;
+        size++;
+    }
+
+    public Object getItemAt(int index){
+        Node tmp = head;
+        int tmpIndex = 0;
+        while(tmpIndex < index){
+            tmp = tmp.next;
+            tmpIndex++;
+        }
+        return tmp.data;
+    }
+
+    public int getSize(){
+        return size;
+    }
+
+    
+}