树的遍历方式总结(山东大学数据结构2016级实验6)

#include <iostream>
#include <stdlib.h>
#include <stack>
#include <string.h>
#include <sstream>
#include <queue>
using namespace std;

//提前声明类
template<class T>
class BinaryTreeNode;

//提前声明类
template<class T>
class BinaryTree;

//自定义异常
class OutOfBound{
public:
    OutOfBound(){
        cout<<"程序出现越界错误！"<<endl;
    }
};

//节点类
template<class T>
class BinaryTreeNode{
public:
    friend class BinaryTree<T>;
    BinaryTreeNode(){LeftChild=NULL;RightChild=NULL;}
    BinaryTreeNode(const T& e){data=e;LeftChild=NULL;RightChild=NULL;}
    BinaryTreeNode(const T& e, BinaryTreeNode *l, BinaryTreeNode *r){
		data = e; LeftChild = l; RightChild = r; 	// data + links 参数
	}
	void SetLeft(BinaryTreeNode<T> *L){LeftChild=L;}
	void SetRight(BinaryTreeNode<T> *R){RightChild=R;}
private:
    T data;
    BinaryTreeNode<T> *LeftChild, *RightChild;
};

//二叉树类
template<class T>
class BinaryTree{
public:
	BinaryTree(){root=NULL;treeSize=0;}
	BinaryTree(const string& str);
	BinaryTreeNode<T>* CreatePreIn(const char *pre,const char *in,int pl,int pr,int il,int ir);
	BinaryTree(string &pre,string &in){
        root=CreatePreIn(pre.c_str(),in.c_str(),0,pre.length(),0,in.length());
        treeSize=pre.length();
	}
	//~BinaryTree(){Erase();}
	bool IsEmpty(){return (root ?false:true);}
	void preOrder(BinaryTreeNode<T>* t);//前序遍历
	void inOrder(BinaryTreeNode<T>* t);//中序遍历
	void postOrder(BinaryTreeNode<T>* t);//后序遍历
	void levelOrder();//层次遍历
	void visit(BinaryTreeNode<T>* t);//访问节点
	BinaryTreeNode<T>* getRoot(){return root;}
    int getSize(){
        return treeSize;
	}
    int height(BinaryTreeNode<T>* t);
private:
    int treeSize;
    BinaryTreeNode<T> *root;
};

//通过字符串构造二叉树
template<class T>
BinaryTree<T>::BinaryTree(const string& str){
    int length=str.length();
    treeSize=length;
    queue<BinaryTreeNode<T>*> qu;
    root=new BinaryTreeNode<T>();
    BinaryTreeNode<T> *pointer=root;
    qu.push(pointer);
    for(int i=1;i<=str.length();i++){
        pointer=qu.front();
        qu.pop();
        pointer->data=str[i-1];
        if(length>=2*i) pointer->LeftChild=new BinaryTreeNode<T>();
        if(length>=2*i+1) pointer->RightChild=new BinaryTreeNode<T>();
        qu.push(pointer->LeftChild);
        qu.push(pointer->RightChild);
        //cout<<pointer->data<<endl;
    }

    cout<<"构造完毕"<<endl;
}

template<class T>//访问函数
void BinaryTree<T>::visit(BinaryTreeNode<T> *t){
    cout<<t->data<<" ";
}

template<class T>//前序遍历
void BinaryTree<T>::preOrder(BinaryTreeNode<T> *t){
    if(t!=NULL){
        BinaryTree::visit(t);
        preOrder(t->LeftChild);
        preOrder(t->RightChild);
    }
}

template<class T>//中序遍历
void BinaryTree<T>::inOrder(BinaryTreeNode<T> *t){
    if(t!=NULL){
        inOrder(t->LeftChild);
        BinaryTree::visit(t);
        inOrder(t->RightChild);
    }
}

template<class T>//后序遍历
void BinaryTree<T>::postOrder(BinaryTreeNode<T> *t){
    if(t!=NULL){
        postOrder(t->LeftChild);
        postOrder(t->RightChild);
        BinaryTree::visit(t);
    }
}

template<class T>//层次遍历
void BinaryTree<T>::levelOrder(){
    queue<BinaryTreeNode<T>*> qu;
    BinaryTreeNode<T>* pointer;
    qu.push(root);
    while(qu.size()!=0){
        pointer=qu.front();
        qu.pop();
        BinaryTree::visit(pointer);
        if(pointer->LeftChild!=NULL){
            qu.push(pointer->LeftChild);
        }
        if(pointer->RightChild!=NULL){
            qu.push(pointer->RightChild);
        }

    }
}

template<class T>//获取高度
int BinaryTree<T>::height(BinaryTreeNode<T>* t){
    if(t==NULL){
        return 0;
    }
    int hl=height(t->LeftChild);
    int hr=height(t->RightChild);
    if(hl>hr){
        return ++hl;
    }else{
        return ++hr;
    }
}

template<class T>//通过前序和中序构造二叉树
BinaryTreeNode<T>* BinaryTree<T>::CreatePreIn(const char *pre,const char *in,int pl,int pr,int il,int ir){
    if(pl>pr) return NULL;
    if(il>ir) return NULL;
    T val=pre[pl];
    if(val==NULL) return NULL;
    BinaryTreeNode<T> *rt=new BinaryTreeNode<T>(pre[pl]);

    int i=il;
    while((in[i]!=val)&&(i<=ir)) i++;
    //cout<<pl<<" "<<pr<<" "<<il<<" "<<ir<<" "<<"val:"<<val<<" i:"<<i<<endl;
    rt->SetLeft(CreatePreIn(pre,in,pl+1,pl+i-il,il,i-1));
    rt->SetRight(CreatePreIn(pre,in,pl+i+1-il,pr,i+1,ir));
    return rt;
}

int main(){
    string str;
    cout<<"请输入你想要创建的二叉树的字符串:"<<endl;
    cin>>str;
    BinaryTree<char> bin(str);
    cout<<"前序遍历:";
    bin.preOrder(bin.getRoot());
    cout<<endl;
    cout<<"中序遍历:";
    bin.inOrder(bin.getRoot());
    cout<<endl;
    cout<<"后序遍历:";
    bin.postOrder(bin.getRoot());
    cout<<endl;
    cout<<"节点数:";
    cout<<bin.getSize()<<endl;
    cout<<"高度:";
    cout<<bin.height(bin.getRoot())<<endl;
    cout<<"请输入你想要创建的第二个二叉树的前序遍历和中序遍历:"<<endl;
    string pre,in;
    cin>>pre;cin>>in;
    BinaryTree<char> bin2(pre,in);
    cout<<"后序遍历:";
    bin2.postOrder(bin2.getRoot());
    cout<<endl;
    cout<<"层次遍历:";
    bin2.levelOrder();
    cout<<endl;
    system("pause");
}