Two methods for creating a two-fork tree and three traversal methods

two ways to create a two-fork tree and three ways to traverse it

Here are two ways to create a method that is worth the data structure above:

The code of the method is as follows:

The structure of the binary tree is defined as follows:

typedefstruct BinaryTreeNode{    char value;    struct  BinaryTreeNode *left;     struct BinaryTreeNode *right;};

-C language version

void CreateBinaryTree(BinaryTreeNode **T){ char data; scanf("%d",&data); if(data==‘#‘) *T=NULL; else { *T=(BinaryTreeNode *)malloc(sizeof(BinaryTreeNode)); (*T)->value=data; CreateBinaryTree(&((*T)->left)); CreateBinaryTree(&((*T)->right)); }}

-C + + version

void  createbinarytree (Binarytreenode * &t) {char  data; cin  >>data; if  (Data== ' # ' ) T=null ; else  {t=new  Binarytreenode; t->value=data; Createbinarytree (T->left); Createbinarytree (T->right); }}

  The return value of the function is null, Note the C language version of the pointer, in C + + in lieu of, the program is more concise, clear C language version, when creating the left and right sub-tree node is, easy to write & (T->left) and & (T->right) note here T and *t difference *t point to B The pointer t of the Inarytreenode node is a pointer to the pointer, *t->left refers to the binarytreenode of the left node C + + version without the C language pointer so responsible, with reference, the operation of T will affect T  

The method two code is as follows:

-C + + version

Binarytreenode * CreateBinaryTree2 () {Binarytreenode *t;CharDataCin>>data;//scanf ();    if(data==' # ') t=NULL;Else{t=NewBinarytreenode;//(Binarytreenode *) malloc (sizeof (Binarytreenode) )t->value=data;        T->left=createbinarytree2 ();    T->right=createbinarytree2 (); }returnT;}

    这种创建方法和方法一的不同之处在于 函数返回值为BinaryTreeNode *    逻辑更加清楚，利用函数的返回值，构建树的左右子树

Three recursive traversal methods, the code is as follows

//first  order void Preordertree (Binarytreenode *t) {if (    T==null) return;    cout<<t->value<< "";    Preordertree (T->left); Preordertree (t->right);}    middle order void Inordertree (Binarytreenode *t) {if (t==null) return;    Inordertree (T->left);    cout<<t->value<< ""; Inordertree (t->right);}    Post-post void Postordertree (Binarytreenode *t) {if (t==null) return;    Postordertree (T->left);    Postordertree (T->right); cout<<t->value<< "";}  

Total code

#include <iostream>#include <stdlib.h>#include <malloc.h>using namespace STD;typedef structbinarytreenode{CharValuestructBinarytreenode *left;structBinarytreenode *right;};/*void createbinarytree (Binarytreenode **t) {char data;    cin>>data;    if (data== ' # ') *t=null;         else {*t= (Binarytreenode *) malloc (sizeof (Binarytreenode));         (*t)->value=data;         Createbinarytree (& (*t)->left);    Createbinarytree (& (*t)->right); }}*/voidCreatebinarytree (Binarytreenode * &t) {CharDataCin>>data;if(data==' # ') t=NULL;Else{t=NewBinarytreenode;         t->value=data;         Createbinarytree (T->left);    Createbinarytree (T->right); }}binarytreenode * CreateBinaryTree2 () {Binarytreenode *t;CharDataCin>>data;if(data==' # ') t=NULL;Else{t=NewBinarytreenode;        t->value=data;        T->left=createbinarytree2 ();    T->right=createbinarytree2 (); }returnT;}voidPreordertree (Binarytreenode *t) {if(t==NULL)return;cout<<T->value<<" ";    Preordertree (T->left); Preordertree (t->right);}voidInordertree (Binarytreenode *t) {if(t==NULL)return; Inordertree (T->left);cout<<T->value<<" "; Inordertree (t->right);}voidPostordertree (Binarytreenode *t) {if(t==NULL)return;    Postordertree (T->left); Postordertree (T->right);cout<<T->value<<" ";}voidMain () {cout<<"---First method of creating a two-fork tree the input sequence is a B C # # # # # # # #----------" <<endl;    cout<< "Please enter the first order to create a two-fork tree sequence, with the ' # ' sign that the node is null, the sequence is as follows:" <<endl;    Binarytreenode *t;    Createbinarytree (T);    cout<< "Method 1 is listed as the first order:";    Preordertree (T);    cout<<endl; cout<< "The central sequence of Method 1 is listed as: ";    Inordertree (T);    cout<<endl;    cout<< "Method 1 of the order sequence is:";    Inordertree (T);    cout<<endl;    cout<< "-----First method of creating two-fork tree the input sequence is a B C # # # # # # # #--------" <<endl;    cout<< "Please enter the first order to create a two-fork tree sequence, with the ' # ' sign that the node is null, the sequence is as follows:" <<endl;    Binarytreenode *t1; T1=createbinarytree2 ();cout<< "Method 2 is listed as the first order:";    Preordertree (T1);        cout<<endl;    cout<< "Method 2 is listed in the preface:";    Inordertree (T1);    cout<<endl;    cout<< "Method 2 of the order sequence is:";    Inordertree (T1); Cout<<endl;}

Two methods for creating a two-fork tree and three traversal methods