fixed linked tree

com/xgiovio/LinkedTreeTest.java

@@ -0,0 +1,46 @@
+package com.xgiovio;
+
+import tree.LinkedTree;
+
+/**
+ * Created with MONSTER.
+ * User: xgiovio
+ * Date: 23/04/2014
+ * Time: 21:46
+ */
+public class LinkedTreeTest {
+
+    public static void main(String[] args) {
+
+        LinkedTree<Integer> a = new LinkedTree<Integer>();
+        System.out.println(a.size());
+        System.out.println(a.isEmpty());
+        System.out.println(a);
+
+
+        a.addRoot(10);
+        System.out.println(a.size());
+        System.out.println(a.isEmpty());
+        System.out.println(a);
+        System.out.println(a.height());
+
+        a.addChild(15,a.root());
+        a.addChild(30,a.root());
+        System.out.println(a.size());
+        System.out.println(a.isEmpty());
+        System.out.println(a);
+
+        a.addChild(100,a.children(a.root()).iterator().next());
+        System.out.println(a.size());
+        System.out.println(a.isEmpty());
+        System.out.println(a);
+
+        System.out.println(a.height());
+
+
+
+
+
+    }
+
+}

tree/LinkedTree.java

@@ -73,9 +73,6 @@ public class LinkedTree <E> implements Tree<E> {
         return vv.getChildren().isEmpty();
     }
 
-
-
-
     public boolean isRoot(Position<E> v) throws InvalidPositionException {
         checkPosition(v);
         return (v == root());
@@ -100,6 +97,17 @@ public class LinkedTree <E> implements Tree<E> {
             preorderPositions(w, pos);
     }
 
+    protected void postorderPositions(Position<E> v, PositionList<Position<E>> pos) throws InvalidPositionException {
+
+        TreePosition<E> a = checkPosition(v);
+
+
+        for (Position<E> w : a.getChildren())
+            postorderPositions(w, pos);
+
+        pos.addLast(a);
+    }
+
     protected TreePosition<E> checkPosition(Position<E> v)
             throws InvalidPositionException {
         if (v == null || !(v instanceof TreePosition) || isEmpty()  )
@@ -138,7 +146,7 @@ public class LinkedTree <E> implements Tree<E> {
                throw new UndeletableNodeException();
            E to_return = root().element();
            root = null;
-           size--;
+           size = 0;
            return to_return;
 
     }
@@ -165,21 +173,25 @@ public class LinkedTree <E> implements Tree<E> {
 
     }
 
-    public int depth ( Position<E> v) {
+    public int depth ( Position<E> v) throws InvalidPositionException{
         TreePosition<E> a = checkPosition(v);
         if (a.getParent() == null)
             return 0;
         return (depth(a.getParent()) + 1);
     }
 
-    public int height ( Position<E> v) {
+    public int height () throws EmptyTreeException{
+       return height_f(root());
+    }
+
+    public int height_f ( Position<E> v) {
         TreePosition<E> a = checkPosition(v);
         if (isExternal(a))
             return 0;
         int max = 0;
         for ( Position<E> w  : a.getChildren()){
-            if (max == 0 || height(w) > max){
-                max = height(w);
+            if (max == 0 || height_f(w) > max){
+                max = height_f(w);
             }
         }
         return 1 + max;
@@ -187,6 +199,23 @@ public class LinkedTree <E> implements Tree<E> {
 
     @Override
     public String toString() {
-        return super.toString();
+        String to_return = "";
+        to_return = to_return + "[";
+        if (size() == 0 )
+            return to_return+= "]";
+
+          NodePositionList<Position<E>> t = new NodePositionList<Position<E>>();
+          postorderPositions(root(),t);
+
+          for (Position<E> w :t){
+              to_return+=w.element() + ",";
+          }
+        to_return = to_return.substring(0, to_return.length()-1);
+
+        return to_return+= "]";
     }
+
+
+
+
 }