public void Posorder()
{
Stack <TwoXTree> stack = new Stack <TwoXTree>();
Stack <bool> stack2 = new Stack <bool>();
TwoXTree node = this;
bool flag;
do
{
while (node != null)
{
stack.Push(node);
stack2.Push(false);
node = node.LeftChild;
}
node = stack.Pop();
flag = stack2.Pop();
if (flag)
{
Visit(node);
node = null;
}
else
{
stack.Push(node);
stack2.Push(true);
node = node.RightChild;
}
} while (node != null || stack.Count > 0);
}
public void Preorder()
{
Stack <TwoXTree> stack = new Stack <TwoXTree>();
Stack <bool> stack2 = new Stack <bool>();
TwoXTree node = this;
bool flag; // used to check if already visit both the left child and the right child of current node
do
{
while (node != null)
{
Visit(node);
stack.Push(node);
stack2.Push(false);
node = node.LeftChild;
}
node = stack.Pop();
flag = stack2.Pop();
if (flag)
{
node = null;
}
else
{
stack.Push(node);
stack2.Push(true);
node = node.RightChild;
}
} while (node != null || stack.Count > 0);
}
public int GetMaxLength()
{
Queue <TwoXTree> treeQueue = new Queue <TwoXTree>();
Queue <int> lengthQueue = new Queue <int>();
TwoXTree node = this;
int length = 0;
treeQueue.Enqueue(node);
lengthQueue.Enqueue(1);
while (treeQueue.Count > 0)
{
node = treeQueue.Dequeue();
length = lengthQueue.Dequeue();
if (node.LeftChild != null)
{
treeQueue.Enqueue(node.LeftChild);
lengthQueue.Enqueue(length + 1);
}
if (node.RightChild != null)
{
treeQueue.Enqueue(node.RightChild);
lengthQueue.Enqueue(length + 1);
}
}
return(length);
}
/// <summary>
/// Get total count
/// </summary>
/// <returns></returns>
public int GetTotalCount()
{
Queue <TwoXTree> queue = new Queue <TwoXTree>();
TwoXTree node = this;
int totalCount = 0;
while (node != null)
{
++totalCount;
if (node.LeftChild != null)
{
queue.Enqueue(node.LeftChild);
}
if (node.RightChild != null)
{
queue.Enqueue(node.RightChild);
}
if (queue.Count > 0)
{
node = queue.Dequeue();
}
else
{
node = null;
}
}
return(totalCount);
}
static void Main(string[] args)
{
string tree = "A(B(C(E(H,),F),D(,I)),J(K,L(M(,N),)))";
TwoXTree twoXTree = TwoXTree.CreateTwoXTree(tree);
int totalCount = twoXTree.GetTotalCount();
int totalCountRecursion = twoXTree.GetTotalCount_Recursion();
int maxLength = twoXTree.GetMaxLength();
int maxLengthRecursion = twoXTree.GetMaxLength_Recursion();
Console.WriteLine("Preorder: ");
twoXTree.Preorder_Recursion();
Console.WriteLine();
twoXTree.Preorder();
Console.WriteLine();
Console.WriteLine("Inorder: ");
twoXTree.Inorder_Recursion();
Console.WriteLine();
twoXTree.Inorder();
Console.WriteLine();
Console.WriteLine("Posorder: ");
twoXTree.Posorder_Recursion();
Console.WriteLine();
twoXTree.Posorder();
Console.WriteLine();
Console.WriteLine("Layer Order: ");
twoXTree.LayerOrder();
Console.WriteLine();
Console.ReadKey();
}
private void Visit(TwoXTree treeNode)
{
if (treeNode == null)
{
return;
}
Console.Write(" ---> {0} ", treeNode.Data);
}
static void Main(string[] args)
{
//从Tree.txt文件读取
string tree = string.Empty;
tree = File.ReadAllText(Environment.CurrentDirectory + "\\Tree.txt");
//string tree = "A(B(C(E(H,),F),D(,I)),J(K,L(M(,N),)))";
TwoXTree twoXTree = TwoXTree.CreateTwoXTree(tree);
int totalCount = twoXTree.GetTotalCount();
int totalCountRecursion = twoXTree.GetTotalCount_Recursion();
int maxLength = twoXTree.GetMaxLength();
int maxLengthRecursion = twoXTree.GetMaxLength_Recursion();
Console.WriteLine("Preorder: ");
twoXTree.Preorder_Recursion();
Console.WriteLine();
twoXTree.Preorder();
Console.WriteLine();
Console.WriteLine("Inorder: ");
twoXTree.Inorder_Recursion();
Console.WriteLine();
twoXTree.Inorder();
Console.WriteLine();
Console.WriteLine("Posorder: ");
twoXTree.Posorder_Recursion();
Console.WriteLine();
twoXTree.Posorder();
Console.WriteLine();
Console.WriteLine("Layer Order: ");
twoXTree.LayerOrder();
Console.WriteLine();
Console.ReadKey();
}
/// <summary>
/// Create a 2XTree
/// </summary>
/// <param name="treeString">eg: A(B(C,D),E(,F(G,)))$</param>
/// <returns></returns>
public static TwoXTree CreateTwoXTree(string treeString)
{
if (String.IsNullOrEmpty(treeString) || treeString.Equals("$"))
{
return(null);
}
var charArray = treeString.ToCharArray();
if (charArray.Count(item => item == '(') != charArray.Count(item => item == ')'))
{
throw new ArgumentException("treeString");
}
Stack <TwoXTree> stack = new Stack <TwoXTree>();
TwoXTree root = new TwoXTree
{
Data = treeString[0].ToString()
};
stack.Push(root);
TwoXTree parent = root, node = root;
bool isLeftNode = true;
for (int i = 1; i < treeString.Length; i++)
{
switch (treeString[i])
{
case '$':
break;
case '(':
stack.Push(node);
parent = node;
isLeftNode = true;
break;
case ')':
stack.Pop();
parent = stack.Peek();
break;
case ',':
isLeftNode = false;
break;
default:
node = new TwoXTree
{
Data = treeString[i].ToString()
};
if (parent != null)
{
if (isLeftNode)
{
parent.LeftChild = node;
}
else
{
parent.RightChild = node;
}
}
break;
}
}
return(root);
}