/// <summary>
/// Get depth of the tree.
/// </summary>
/// <typeparam name="T">The type of value the node contains.</typeparam>
/// <param name="tree">A tree to calculte depth.</param>
/// <returns>The depth of the tree.</returns>
/// <exception cref="ArgumentNullException">When <paramref name="tree"/> is <see langword="null"/>.</exception>
public static int GetDepth <T>(this ITreeBase <T> tree)
{
int GetDepthInternal(ITreeBase <T> node, int depth)
{
int result = depth;
foreach (ITreeBase <T> child in node)
{
int tempDepth = GetDepthInternal(child, depth + 1);
if (tempDepth > result)
{
result = tempDepth;
}
}
return(result);
}
switch (tree ?? throw ExceptionHelper.ArgumentNull(nameof(tree)))
{
case IBinaryTree <T> binaryTree:
return(GetDepthBinary(binaryTree));
default:
return(GetDepthInternal(tree, 1));
}
}
protected void VisitAllChildren(ITreeBase <TPayload> tree)
{
IEnumerable <ITreeBase <TPayload> > children = tree.Children;
foreach (ITreeBase <TPayload> child in children)
{
child.Accept(this);
}
}
/// <summary>
/// Get an <see cref="IEnumerable{T}"/> with order of depth-first-search.
/// </summary>
/// <typeparam name="T">The type of value the node contains.</typeparam>
/// <param name="tree">A tree to enumerate.</param>
/// <returns>An <see cref="IEnumerable{T}"/> with order of depth-first-search.</returns>
/// <exception cref="ArgumentNullException">When <paramref name="tree"/> is <see langword="null"/>.</exception>
public static IEnumerable <ITreeBase <T> > AsDFSEnumerable <T>(this ITreeBase <T> tree)
{
switch (tree ?? throw ExceptionHelper.ArgumentNull(nameof(tree)))
{
case IBinaryTree <T> binaryTree:
return(AsPreOrderEnumerableIterator(binaryTree));
default:
return(AsDFSEnumerableIterator(tree));
}
}
/// <summary>
/// Get an iterator with order of depth-first-search.
/// </summary>
/// <typeparam name="T">The type of value the node contains.</typeparam>
/// <param name="tree">A tree to enumerate.</param>
/// <returns>An <see cref="IEnumerable{T}"/> with order of depth-first-search.</returns>
private static IEnumerable <ITreeBase <T> > AsDFSEnumerableIterator <T>(ITreeBase <T> tree)
{
Stack <ITreeBase <T> > nodes = new Stack <ITreeBase <T> >();
nodes.Push(tree);
while (nodes.Count != 0)
{
ITreeBase <T> current = nodes.Pop();
yield return(current);
foreach (var child in current.Reverse())
{
nodes.Push(child);
}
}
}
protected override void DefaultOperation(ITreeBase <TPayload> tree)
{
TPayload payload = tree.Payload;
Result = Accumulate(payload, Result);
}
protected override void DefaultOperation(ITreeBase <TPayload> tree)
{
Count++;
}
public TRec WithChild(ITreeBase <TPayload> child)
{
_chilren.Add(child);
return(GetMe());
}
/// <summary>
/// Get an <see cref="IEnumerable{T}"/> with order of depth-first-search with current path.
/// </summary>
/// <typeparam name="T">The type of value the node contains.</typeparam>
/// <param name="tree">A tree to enumerate.</param>
/// <returns>An <see cref="IEnumerable{T}"/> with order of depth-first-search with current path.</returns>
/// <exception cref="ArgumentNullException">When <paramref name="tree"/> is <see langword="null"/>.</exception>
public static IEnumerable <(ITreeBase <T> Node, IReadOnlyCollection <ITreeBase <T> > Path)> AsDFSWithPath <T>(this ITreeBase <T> tree)
=> AsDFSWithPathIterator(tree ?? throw ExceptionHelper.ArgumentNull(nameof(tree)));
protected void DoOpAndVisitAllChildren(ITreeBase <TPayload> tree, Action <ITreeBase <TPayload> > operation)
{
operation(tree);
VisitAllChildren(tree);
}
public virtual void Visit(ITreeBase <TPayload> tree)
{
DoOpAndVisitAllChildren(tree, DefaultOperation);
}
protected virtual void DefaultOperation(ITreeBase <TPayload> tree)
{
}
