//возвращает кортеж из 2 элементов (узел, родитель)
private Tuple <Node, Node> _Find(int key)
{
if (root == null)
{
return(new Tuple <Node, Node>(null, null));
}
Node current = root;
Node parent = null;
while (key != current.GetKey())
{
if (key < current.GetKey())
{
if (current.GetLeft() == null)
{
return(new Tuple <Node, Node>(null, current));
}
parent = current;
current = current.GetLeft(); //спуск
}
else
{
if (current.GetRight() == null)
{
return(new Tuple <Node, Node>(null, current));
}
parent = current;
current = current.GetRight(); //спуск
}
}
return(new Tuple <Node, Node>(current, parent));
}
public void Add(Node node)
{
Tuple <Node, Node> tup = _Find(node.GetKey());
Node exNode = tup.Item1, parent = tup.Item2;
if (exNode == null)
{
if (parent == null)
{
root = node;
}
else if (parent.GetKey() > node.GetKey())
{
parent.SetLeft(node);
}
else
{
parent.SetRight(node);
}
}
else
{
node.SetLeft(exNode.GetLeft());
node.SetRight(exNode.GetRight());
if (parent.GetLeft() == exNode)
{
parent.SetLeft(node);
}
else
{
parent.SetRight(node);
}
}
}
static void Main(string[] args)
{
BinaryTree tree = new BinaryTree();
Console.WriteLine("Enter \"add <value>\" to add node;");
Console.WriteLine("Enter \"find <value>\" to find node;");
Console.WriteLine("Enter \"remove <value>\" to remove node;");
Console.WriteLine("Enter \"pre\" to PreOrder traversal;");
Console.WriteLine("Enter \"in\" to InOrder traversal;");
Console.WriteLine("Enter \"post\" to PostOrder traversal;");
Console.WriteLine("Enter \"exit\" to terminate a programm.");
do
{
Console.Write("Enter command: ");
string command = Console.ReadLine();
string[] data = command.Split(new char[] { ' ' },
StringSplitOptions.RemoveEmptyEntries);
switch (data[0])
{
case "add":
case "find":
case "remove":
if (data.Length != 2)
{
Console.WriteLine("Invalid parameters count"); break;
}
int value; bool isParse = int.TryParse(data[1], out value);
if (!isParse)
{
Console.WriteLine("Not valid number"); break;
}
if (data[0] == "add")
{
tree.Add(new Node(value));
}
else if (data[0] == "find")
{
Node node = tree.Find(value);
if (node != null)
{
Console.WriteLine("Found {0} node", node.GetKey());
}
else
{
Console.WriteLine("Node is not found");
}
}
else
{
Node node = tree.Remove(value);
if (node != null)
{
Console.WriteLine("Removed {0} node", node.GetKey());
}
else
{
Console.WriteLine("Node is not found");
}
}
break;
case "pre": tree.PreOrderTraversal(); break;
case "in": tree.InOrderTraversal(); break;
case "post": tree.PostOrderTraversal(); break;
case "exit": return;
default: Console.WriteLine("Command is not recognised"); break;
}
} while (true);
}