/// <summary>
/// Performs the action on all nodes of the subtree in a pre-order, right-to-left fashion.
/// </summary>
private static void PreOrderRightToLeftVisitor <TKey, TValue>(BinarySearchTreeMapNode <TKey, TValue> root, Action <BinarySearchTreeMapNode <TKey, TValue> > action)
{
if (root == null)
{
return;
}
action(root);
PreOrderRightToLeftVisitor(root.Right, action);
PreOrderRightToLeftVisitor(root.Left, action);
}
/// <summary>
/// Recursively visits all nodes of the given subtree in the specified order and applies the given action on them. Level-order traversal is iterative.
/// </summary>
/// <typeparam name="TKey">The data type of the key of the <see cref="BinarySearchTreeMapNode{TKey, TValue}"/>.</typeparam>
/// <typeparam name="TValue">The data type of the value of the <see cref="BinarySearchTreeMapNode{TKey, TValue}"/>.</typeparam>
/// <param name="root">The root of the subtree for traversal.</param>
/// <param name="action">The action to perform on each node.</param>
/// <param name="traversalMode">The way in which the subtree is traversed.</param>
public static void ForEachRecursive <TKey, TValue>(this BinarySearchTreeMapNode <TKey, TValue> root, Action <BinarySearchTreeMapNode <TKey, TValue> > action, TraversalMode traversalMode = TraversalMode.InOrder)
{
if (root == null)
{
throw new ArgumentNullException("root");
}
if (action == null)
{
throw new ArgumentNullException("action");
}
switch (traversalMode)
{
case TraversalMode.InOrder:
InOrderVisitor(root, action);
break;
case TraversalMode.InOrderRightToLeft:
InOrderRightToLeftVisitor(root, action);
break;
case TraversalMode.PreOrder:
PreOrderVisitor(root, action);
break;
case TraversalMode.PreOrderRightToLeft:
PreOrderRightToLeftVisitor(root, action);
break;
case TraversalMode.PostOrder:
PostOrderVisitor(root, action);
break;
case TraversalMode.PostOrderRightToLeft:
PostOrderRightToLeftVisitor(root, action);
break;
case TraversalMode.LevelOrder:
LevelOrderVisitor(root, action);
break;
case TraversalMode.LevelOrderRightToLeft:
LevelOrderRightToLeftVisitor(root, action);
break;
default:
InOrderVisitor(root, action);
break;
}
}
/// <summary>
/// Performs the action on all nodes of the subtree in a level-order, right-to-left fashion.
/// </summary>
private static void LevelOrderRightToLeftVisitor <TKey, TValue>(BinarySearchTreeMapNode <TKey, TValue> root, Action <BinarySearchTreeMapNode <TKey, TValue> > action)
{
if (root == null)
{
return;
}
action(root);
var queue = new Queue <BinarySearchTreeMapNode <TKey, TValue> >();
if (root.Right != null)
{
action(root.Right);
queue.Enqueue(root.Right);
}
if (root.Left != null)
{
action(root.Left);
queue.Enqueue(root.Left);
}
while (queue.Count > 0)
{
var curNode = queue.Dequeue();
if (curNode.Right != null)
{
action(curNode.Right);
queue.Enqueue(curNode.Right);
}
if (curNode.Left != null)
{
action(curNode.Left);
queue.Enqueue(curNode.Left);
}
}
}
