二叉树遍历：先序、中序、后序和层次遍历

public class BinaryNode

public class BinaryTree

BinaryNode n1 = new BinaryNode();

n1.Data = 27;

BinaryNode n2 = new BinaryNode();

n2.Data = 83;

BinaryNode n3 = new BinaryNode();

n3.Data = 123;

BinaryNode n4 = new BinaryNode();

n4.Data = 98;

BinaryNode n5 = new BinaryNode();

n5.Data = 94;

BinaryNode n6 = new BinaryNode();

n6.Data = 48;

BinaryNode n7 = new BinaryNode();

n7.Data = 61;

n1.Left = n2;

n1.Right = n3;

n1.Left.Left = n4;

n1.Left.Right = n5;

n1.Right.Right = n6;

n1.Right.Right.Left = n7;

BinaryTree bTree = new BinaryTree();

Console.WriteLine("Pre Order Binary Tree:");

bTree.PreOrder(n1);

Console.WriteLine("Midd Order Binary Tree:");

bTree.MidOrder(n1);

Console.WriteLine("After Order Binary Tree:");

bTree.AfterOrder(n1);

Console.WriteLine("Layer Order Binary Tree:");

bTree.LayerOrder(n1);

Console.ReadLine();