add copy

src/StruttureDati/SimpleList/ListNI.java

@@ -0,0 +1,35 @@
+public class ListNI extends SimpleList{
+
+    public ListNI(){
+        super();
+    }
+
+    public void addAt(int pos, Object elem){
+        if(pos==0)
+            addHead(elem);
+        else if(!isEmpty()){
+            Object headElem=head();
+            remHead();
+            addAt(pos-1, elem);
+            addHead(headElem);
+        }
+    }
+
+    public void remAt(int pos, Object elem){
+        if(pos==0)
+            remHead();
+        else if(!isEmpty()){
+            Object headElem=head();
+            remHead();
+            remAt(pos-1, elem);
+            addHead(headElem);
+        }
+    }
+
+    public ListNI copy(){
+        ListNI list = new ListNI();
+        list.node=this.node;
+        list.len=this.len;
+        return list;
+    }
+}