源代码:
#include<iostream.h>
const int QSize=100;
struct BiNode
{
char data;
BiNode *lchild,*rchild;
};
class BiTree
{
BiNode*root;//指向根结点的头指针
BiNode*Creat(BiNode *bt);//构造函数,建立一棵二叉树
void Release(BiNode *bt);//析构函数
void PreOrder(BiNode *bt);//前序遍历
void InOrder(BiNode *bt);//中序遍历
void PostOrder(BiNode*bt);//后序遍历
public:
BiTree(){root=Creat(root);}
~BiTree(){Release(root);}
void PreOrder(){PreOrder(root);}
void InOrder(){InOrder(root);}
void PostOrder(){PostOrder(root);}
void LeverOrder();//层序遍历,用顺序队列来实现操作
};
BiNode *BiTree::Creat(BiNode *bt)
{
char ch;
cin>>ch;
if(ch=='#')return NULL;
else
{
bt=new BiNode;
bt->data=ch;
bt->lchild=Creat(bt->lchild);
bt->rchild=Creat(bt->rchild);
}
return bt;
}
void BiTree::Release(BiNode *bt)
{
if(bt!=NULL)
{
Release(bt->lchild);
Release(bt->rchild);
delete bt;
}
}
void BiTree::PreOrder(BiNode *bt)
{
if(bt==NULL)return;
else
{
cout<<bt->data<<" ";
PreOrder(bt->lchild);
PreOrder(bt->rchild);
}
}
void BiTree::InOrder(BiNode *bt)
{
if(bt==NULL)return;
else
{
InOrder(bt->lchild);
cout<<bt->data<<" ";
InOrder(bt->rchild);
}
}
void BiTree::PostOrder(BiNode *bt)
{
if(bt==NULL)return;
else
{
PostOrder(bt->lchild);
PostOrder(bt->rchild);
cout<<bt->data<<" ";
}
}
void BiTree::LeverOrder()
{
BiNode *q,*Q[QSize];
int front=-1,rear=-1;
if(root==NULL)return;
Q[++rear]=root;
while(front!=rear)
{
q=Q[++front];
cout<<q->data<<" ";
if(q->lchild!=NULL) Q[++rear]=q->lchild;
if(q->rchild!=NULL) Q[++rear]=q->rchild;
}
}
int main()
{
cout<<"请输入创建一棵二叉树的结点数据:"<<endl;
BiTree T;
cout<<"前序遍历"<<endl;
T.PreOrder();
cout<<endl;
cout<<"中序遍历"<<endl;
T.InOrder();
cout<<endl;
cout<<"后序遍历"<<endl;
T.PostOrder();
cout<<endl;
cout<<"层序遍历"<<endl;
T.LeverOrder();
cout<<endl;
return 0;
}
运行结果:
