算法导论第十章-二叉树的实现

BintreeNode.h二叉树节点头文件

#include<iostream>
using namespace std;
class Bintree;
class BintreeNode
{
private:
	friend Bintree;
	int key;
	BintreeNode* left,*right;
public:
	BintreeNode()
	{
		right=NULL;
		left=NULL;
	}
	BintreeNode(int num):key(num),left(NULL),right(NULL){}
	BintreeNode(int num,BintreeNode* L,BintreeNode *R):key(num),left(L),right(R)
	{}
	int Getkey()
	{
		return key;
	}
	BintreeNode* Getleft()
	{
		return left;
	}
	BintreeNode* Getright()
	{
		return right;
	}

};

 

Bintree.h二叉树文件

#include"BintreeNode.h"
#include<stack>
class Bintree
{
private:
	BintreeNode *root;
public:
	Bintree():root(NULL){}
	~Bintree()
	{
		MakeEmpty(root);
	}
	void MakeEmpty(BintreeNode *node)
	{
		BintreeNode *p=node;
		if(p->left==NULL&&p->right==NULL)
		{
			delete p;
			return ;
		}
		if(p->left!=NULL)
		{
			MakeEmpty(p->left);
		}
		if(p->right!=NULL)
		{
			MakeEmpty(p->right);
		}
	}
	bool Insert(int num)
	{
		BintreeNode *p=new BintreeNode(num);
		BintreeNode*q=root;
		if(root==NULL)
		{
			root=p;
			return 1;
		}
		while(1)
		{
			if(q->key==num)
			{
				cout<<num<<" is exit!"<<endl;
				return 0;
			}
			else if(q->key>=num)
			{
				if(q->left!=NULL)
					q=q->left;
				else
				{
						q->left=p;
						return 1;
				}

			}
			else 
			{
				if(q->right!=NULL)
					q=q->right;
				else
				{
					q->right=p;
					return 1;
				}
			}
		}
	}
	BintreeNode*Find(int num)
	{
		BintreeNode*p=root;
		while(p!=NULL)
		{
			if(p->key==num)
			{
				return p;
			}
			else if(p->key>num)
			{
				p=p->left;
			}
			else 
			{
				p=p->right;
			}
		}
		return NULL;
	}
	BintreeNode* GetParent(BintreeNode*node)
	{
		if(node->key==root->key)
		{
			cout<<"root node doesn't have parent!"<<endl;
			return NULL;
		}
		BintreeNode* p=root,*q=p;
		while(p!=node)
		{
			if(p->key==node->key)
			{
				break;
			}
			else if(p->key>node->key)
			{
				q=p;
				p=p->left;
			}
			else
			{
				q=p;
				p=p->right;
			}
		}
		return q;
	}
	void InOrder(BintreeNode* node)
	{
		BintreeNode*p=node;
		if(p!=NULL)
		{
			InOrder(p->left);
			cout<<p->key<<" ";
			InOrder(p->right);
		}
	}
	void PreOrder(BintreeNode* node)
	{
		BintreeNode*p=node;
		if(p!=NULL)
		{
			cout<<node->key<<" ";
			PreOrder(p->left);
			PreOrder(p->right);
		}
	}
	void PostOrder(BintreeNode* node)
	{
		BintreeNode*p=node;
		if(p!=NULL)
		{
			PostOrder(p->left);
			PostOrder(p->right);
			cout<<node->key<<" ";
		}
	}
	//非递归中序遍历
	void NonReInOrder(BintreeNode* node)
	{
		BintreeNode*p=node;
		stack<BintreeNode*>s;
		s.push(p);
		bool flag=0;
		while(!s.empty())
		{
			p=s.top();
			//flag标志位。如果flag为0则沿着树向下遍历，如果flag为1则沿着树向上遍历
			if(flag==0)
			{
				if(p->left==NULL)
				{
					cout<<p->key<<" ";
					s.pop();
					if(p->right==NULL)
					{
						if(s.empty())
						{
							break;
						}
						p=s.top();
						cout<<p->key<<" ";
						s.pop();
						flag=1;
					}
					else
					{
						s.push(p->right);
						p=s.top();
						flag=0;
					}
				}
				else
				{
					s.push(p->left);
					flag=0;
				}
			}
			//沿着树向上遍历左孩子
			if(flag==1)
			{
				if(p->right==NULL)
				{
					if(s.empty())
					{
						break;
					}
					flag=1;
					p=s.top();
					cout<<p->key<<" ";
					s.pop();
				}
				s.push(p->right);
				flag=0;
			}
		}
		cout<<"this is the end!"<<endl;
	}
	BintreeNode*GetRoot()
	{
		return root;
	}
	BintreeNode*GetLeft(BintreeNode*node)
	{
		if(node->left!=NULL)
		{
			return node->left;
		}
		return NULL;
	}
	BintreeNode*GetRight(BintreeNode*node)
	{
		if(node->right!=NULL)
		{
			return node->left;
		}
		return NULL;
	}
	int Height(BintreeNode*node)
	{
		if(node==NULL)
		{
			return -1;
		}
		int lheight=Height(node->left);
		int rheight=Height(node->right);
		return 1+(lheight>rheight?lheight:rheight);
	}

};

 

main.cpp

#include"Bintree.h"
int main()
{
	int i;
	int a[10]={4,5,2,37,1,8,9,12,78,54};
	Bintree tree;
	for(i=0;i<10;i++)
	{
		tree.Insert(a[i]);
	}
	tree.InOrder(tree.GetRoot());
	cout<<endl;
	tree.NonReInOrder(tree.GetRoot());
	cout<<endl;
	tree.PreOrder(tree.GetRoot());
	cout<<endl;
	tree.PostOrder(tree.GetRoot());
	cout<<endl;
	cout<<tree.Find(5)->Getkey()<<endl;
	cout<<tree.Height(tree.GetRoot())<<endl;
	return 0;
}