二叉树学习

#include<iostream>
#include<string.h>
using namespace std;
struct Node
{
    char data;
    Node* left;
    Node* right;
    Node():left(NULL),right(NULL){}
    Node(char x,Node* l=NULL,Node* r=NULL){data=x;}
};
class Tree
{
public:
    Tree():root(NULL){}
    ~Tree(){Destroy(root);}

    //广义表创建
    //void createTree(createTree(root);)
    void Destroy(Node* root);
    void createBinTree_pre_in(const char *pre, const char *in)
    {
        int n = strlen(pre);
        createTree_pre_in(root, pre, in, n);
    }
    void createTree_pre_in(Node*& cur,const char* pre,const char* in,int n);//先序&中序遍历
    //先序遍历
    void Pre_order(){pre_order(root);}
    void pre_order(Node* root);
    //后续遍历
    void Post_order(){post_order(root);}
    void post_order(Node* root);
private:
    Node* root;
};
void Tree::createTree_pre_in(Node*& cur,const char* pre,const char* in,int n)
{
    if (n <= 0)
        {
            cur = NULL;
            return;
        }
    int k=0;
    while(pre[0]!=in[k]){k++;}
    cur=new Node(in[k]);
    createTree_pre_in(cur->left,pre+1,in,k);
    createTree_pre_in(cur->right,pre+k+1,in+k+1,n-k-1);
}
void Tree::pre_order(Node* root){
    if (root != NULL)
    {
        cout << root->data << " ";
        pre_order(root->left);
        pre_order(root->right);
    }
}
void Tree::post_order(Node* root){
    if(root!=NULL){
        post_order(root->left);
        post_order(root->right);
        cout<<root->data<<" ";
    }
}
void Tree::Destroy(Node* root){
    if(root==NULL)
        return;
    Destroy(root->left);
    Destroy(root->right);
    delete root;
}
int main()
{
    char pre[]="12473568";
    char in[]="47215386";
    Tree T;
    T.createBinTree_pre_in(pre,in);
    T.Pre_order();
    cout<<endl;
    T.Post_order();
    cout<<endl;
    T.~Tree();
    cout<<"destoried"<<endl;

}