输入C，先序创建二叉树，#表示空节点；
输入H：计算二叉树的高度；
输入L：计算二叉树的叶子个数；
输入N：计算二叉树节点总个数；
输入1：先序遍历二叉树；
输入2：中序遍历二叉树；
输入3：后续遍历二叉树；
输入F：查找值=x的节点的个数；
输入P：以缩格文本形式输出所有节点。
#include <iostream>
using namespace std;
struct TreeNode{
char data;
TreeNode *leftChild,*rightChild;
TreeNode(){
leftChild=NULL;
rightChild=NULL;
}
TreeNode(char x,TreeNode *l=NULL,TreeNode *r=NULL){
data=x;leftChild=l;rightChild=r;
}
};
class Tree{
private:
TreeNode *root;
char endTag;
void createTree(TreeNode *&subTree);
void preOrder(TreeNode *subTree);
void inOrder(TreeNode *subTree);
void postOrder(TreeNode *subTree);
int height(TreeNode *subTree);
int leaf(TreeNode *subTree,int &cnt);
int node(TreeNode *subTree);
int Find(TreeNode *subTree,int &cnt);
void show(TreeNode *subTree,int cnt);
public:
Tree():root(NULL){}
Tree(char c):endTag(c),root(NULL){}
void createTree(){
createTree(root);
}
void preOrder(){
preOrder(root);
}
void inOrder(){
inOrder(root);
}
void postOrder(){
postOrder(root);
}
int height(){
return height(root);
}
int leaf(int &cnt){
return leaf(root,cnt);
}
int node(){
return node(root);
}
int Find(int &cnt){
return Find(root,cnt);
}
void show(int cnt){
show(root,cnt);
}
};
void Tree::createTree(TreeNode *&subTree){
char c;
cin>>c;
if(c!=endTag){
subTree=new TreeNode(c);
createTree(subTree->leftChild);
createTree(subTree->rightChild);
}
}
void Tree::preOrder(TreeNode *subTree){
if(subTree!=NULL){
cout<<subTree->data<<" ";
preOrder(subTree->leftChild);
preOrder(subTree->rightChild);
}
}
void Tree::inOrder(TreeNode *subTree){
if(subTree!=NULL){
inOrder(subTree->leftChild);
cout<<subTree->data<<" ";
inOrder(subTree->rightChild);
}
}
void Tree::postOrder(TreeNode *subTree){
if(subTree!=NULL){
postOrder(subTree->leftChild);
postOrder(subTree->rightChild);
cout<<subTree->data<<" ";
}
}
int Tree::height(TreeNode *subTree){
if(subTree!=NULL){
return 1+(height(subTree->leftChild)>height(subTree->rightChild)?height(subTree->leftChild):height(subTree->rightChild));
}
else return 0;
}
int Tree::leaf(TreeNode *subTree,int &cnt){
if(subTree!=NULL){
if(subTree->leftChild==NULL&&subTree->rightChild==NULL){
cnt++;
}
leaf(subTree->leftChild,cnt);
leaf(subTree->rightChild,cnt);
}
return cnt;
}
int Tree::node(TreeNode *subTree){
if(subTree!=NULL){
return 1+node(subTree->leftChild)+node(subTree->rightChild);
}
else return 0;
}
int Tree::Find(TreeNode *subTree,int &cnt){
if(subTree!=NULL){
if(subTree->data=='A'){
cnt++;
}
Find(subTree->leftChild,cnt);
Find(subTree->rightChild,cnt);
}
return cnt;
}
void Tree::show(TreeNode *subTree,int cnt){
if(subTree!=NULL){
for(int i=0;i<cnt;i++){
cout<<" ";
}
cout<<subTree->data<<endl;
show(subTree->leftChild,cnt+1);
show(subTree->rightChild,cnt+1);
}
}
int main()
{
Tree t('#');int cnt=0,cn=0;
t.createTree();
t.preOrder();
cout<<endl;
t.inOrder();
cout<<endl;
t.postOrder();
cout<<endl;
cout<<t.height()<<endl;
cout<<t.node()<<endl;
cout<<t.leaf(cnt)<<endl;
cout<<t.Find(cn)<<endl;
t.show(0);
return 0;
}