Trees: input options, extra info etc

Author: lee-naish

src/algorithms/controllers/TTFTreeInsertion.js

@@ -10,7 +10,7 @@ export default {
   initVisualisers() {
     return {
       tree: {
-        instance: new NTreeTracer('n-tree', null, 'Tree View'),
+        instance: new NTreeTracer('n-tree', null, '2-3-4 Tree'),
         order: 0,
       },
     };

src/algorithms/controllers/TTFTreeSearch.js

@@ -286,4 +286,4 @@ export default {
     this.search(chunker, root, target);
   },
 
-};
+};

src/algorithms/controllers/binaryTreeInsertion.js

@@ -36,6 +36,10 @@ export default {
       (vis, elements) => {
         vis.array.set(elements);
         // vis.array.select(0); // the index of root element is 0
+        // make a bit more room for tree
+        vis.graph.setSize(2.5);
+        vis.graph.setZoom(0.8);
+        vis.array.setZoom(0.9);
       },
       [nodes],
     );

src/algorithms/extra-info/AVLInfo.md

@@ -21,7 +21,7 @@ W3Schools Link: [**AVL Trees**][G4GLink]
 With insertion of three distinct keys there are six orders in which the
 keys may appear.  How many different AVL trees are there with three
 given distinct keys? Explore how insertion takes place for the six
-different orders.
+different orders and compare this with simple binary search trees.
 
 In the background it says that unbalance can only be caused by insertion
 into a grandchild of a node.  Why can't it be caused by just adding a

src/algorithms/extra-info/BSTInfo.md

@@ -18,4 +18,10 @@ a:hover{
 Geeks for Geeks Link: [**Binary Search Tree**][G4GLink]
 
 
-[G4GLink]: https://www.geeksforgeeks.org/binary-search-tree-data-structure/
+[G4GLink]: https://www.geeksforgeeks.org/binary-search-tree-data-structure/
+
+## Exercises/Exploration
+
+The "balanced" input option is designed to produce a best possible
+ordering for building a binary search tree.  Can you figure out how it
+works? Can you design an algorithm to produce this ordering?

src/algorithms/extra-info/TTFInfo.md

@@ -1 +1,32 @@
-# 2-3-4 Trees
+<style>
+a:link {
+    color: #1e28f0;
+}
+a:visited{
+    color: #3c1478;
+}
+a:hover{
+    color: #1e288c;
+}
+</style>
+
+## Extra Info
+
+-----
+
+Geeks for Geeks Link: [**2-3-4 Tree**][G4GLink]
+
+
+[G4GLink]: https://www.geeksforgeeks.org/dsa/2-3-4-tree/
+
+
+## Exercises/Exploration
+
+The "balanced" input option produces optimal ordering for simple binary
+search trees, not for 2-3-4 trees.  For the keys 1-11, both sorted and
+"balanced" orderings result in a 2-3-4 tree of height three. Can you
+find an ordering that results in a 2-3-4 tree of height two?
+
+Compare and contrast how 2-3-4 trees, AVL trees and simple binary search
+trees behave for sorted input and "balanced" input.
+