"use strict";

//var tab = window.open();   

myMain();

function myMain() {
  
  // just a "random" binary tree 
  // has no less/greater order on values
  var tree = makeCell("alpha");  // Cell tree = new Cell("alpha");
  tree.LC = makeCell("beta");    // tree.LC = new Cell("beta");
  tree.RC = makeCell("gamma");
  tree.LC.LC = makeCell("delta");
  tree.LC.RC = makeCell("epsilon");
  tree.RC.RC = makeCell("theta");
  
  /* // binary tree that is BST ordered
  var tree = makeCell("delta");  
  tree.LC = makeCell("alpha"); 
  tree.RC = makeCell("gamma");
  tree.LC.RC = makeCell("beta");
  tree.RC.LC = makeCell("epsilon");
  tree.RC.RC = makeCell("theta");
  */
  
  /* // another BST, same values diff structure
  var tree = makeCell("gamma");  
  tree.LC = makeCell("beta"); 
  tree.RC = makeCell("theta");
  tree.LC.RC = makeCell("epsilon");
  tree.LC.LC = makeCell("alpha");
  tree.LC.RC.LC = makeCell("delta");
  */
  
  alert( "IN ORDER traversal" );
  inOrder(tree);
  
  alert( "PRE ORDER traversal" );
  preOrder(tree);
  
  alert( "POST ORDER traversal" );
  postOrder(tree);
  //tab.document.close();
}

function inOrder( cel ) { 
  if (cel===null) { return; }
  inOrder(cel.LC);
  alert(cel.val);  // root is handled in between children
  inOrder(cel.RC);
}

function preOrder( cel ) {
  if (cel===null) { return; }
  alert(cel.val);  // root is handled pre children
  preOrder(cel.LC);
  preOrder(cel.RC);
}

function postOrder ( cel ) {
  if (cel===null) { return; }
  postOrder(cel.LC);
  postOrder(cel.RC);
  alert(cel.val);  // root is handled post children
}

function makeCell ( v ) {
  var cell = {
    val: v,
    LC: null,
    RC: null   
  };
  return cell;
}