C++二叉树基础操作：创建、遍历与节点统计

 1 #include<iostream.h>
  2 struct tree
  3 {
  4     int data;
  5     tree *left,*right;
  6 };
  7 class Btree
  8 {
  9     static int n;
 10     static int m;
 11 public:
 12     tree *root;
 13     Btree()
 14     {
 15         root=NULL;
 16     }
 17     void create_Btree(int);
 18     void Preorder(tree *);                  //先序遍历
 19     void inorder(tree *);                   //中序遍历
 20     void Postorder(tree *);                 //后序遍历
 21     void display1() {Preorder(root); cout<<endl;}
 22     void display2() {inorder(root);cout<<endl;}
 23     void display3() {Postorder(root); cout<<endl;}  
 24     int count(tree *);                      //计算二叉树的个数
 25     int findleaf(tree *);                   //求二叉树叶子的个数
 26     int findnode(tree *);                   //求二叉树中度数为1的结点数量,这是当初考数据结构时候的最后一道题目
 27 };                                          
 28 int Btree::n=0;
 29 int Btree::m=0;
 30 void Btree::create_Btree(int x)