二叉树的遍历（递归与非递归）

标签：二叉树   遍历   数据结构   非递归   递归   

#include<stdio.h>
#include<malloc.h>
#include<iostream>
#include<stack>
#include<queue>
using namespace std;

typedef struct BiTNode
{
    char data,tag;
    struct BiTNode *lchild,*rchild;
}BiTNode,*BiTree;

int createBiTree(BiTree &T)//create tree by pre order
{
    char data;
    scanf("%c",&data);
    if(data=='#')
    {
        T=NULL;
    }
    else
    {
        T=(BiTree)malloc(sizeof(BiTNode));
        T->data=data;
        createBiTree(T->lchild);
        createBiTree(T->rchild);
    }
    return 0;
}

void visit(BiTree T)
{
    if(T->data!='#')
    {
        printf("%c ",T->data);
    }
}

void preOrder(BiTree T)
{
    if(T!=NULL)
    {
        visit(T);
        preOrder(T->lchild);
        preOrder(T->rchild);
    }
}

void interOrder(BiTree T)
{
    if(T!=NULL)
    {
        interOrder(T->lchild);
        visit(T);
        interOrder(T->rchild);
    }
}

void postOrder(BiTree T)
{
    if(T!=NULL)
    {
        postOrder(T->lchild);
        postOrder(T->rchild);
        visit(T);
    }
}

void preNROrder(BiTree T)
{
    stack<BiTree> stack;
    BiTree p=T;
    while(p!=NULL||!stack.empty())
    {
        if(p!=NULL)
        {
            stack.push(p);
            printf("%c ",p->data);
            p=p->lchild;
        }
        else
        {
            p=stack.top();
            stack.pop();
            p=p->rchild;
        }
    }
}

void interNROrder(BiTree T)
{
    stack<BiTree> stack;
    BiTree p=T;
    while(p!=NULL||!stack.empty())
    {
        if(p!=NULL)
        {
            stack.push(p);
            p=p->lchild;
        }
        else
        {
            p=stack.top();
            printf("%c ",p->data);
            stack.pop();
            p=p->rchild;
        }
    }
}

void postNROrder(BiTree T)
{
    stack<BiTree> stack;
    BiTree p=T;
    while(p!=NULL||!stack.empty())
    {
        while(p!=NULL)
        {
            p->tag='L';
            stack.push(p);
            p=p->lchild;
        }
        while(!stack.empty()&&(stack.top())->tag=='R')
        {
            p=stack.top();
            stack.pop();
            printf("%c ",p->data);
        }
        if(stack.size()==0)
        {
            break;
        }
        if(!stack.empty())
        {
            p=stack.top();
            p->tag='R';
            p=p->rchild;
        }
    }
}

void levelTraverse(BiTree T)
{
    BiTree p=T;
    queue<BiTree> queue;
    queue.push(p);
    while(!queue.empty())
    {
        p=queue.front();
        printf("%c ",p->data);
        queue.pop();
        if(p->lchild!=NULL)
        {
            queue.push(p->lchild);
        }
        if(p->rchild!=NULL)
        {
            queue.push(p->rchild);
        }
    }
}

int main()
{
    BiTree T;
    createBiTree(T);

    printf("pre order traverse:\n");
    preOrder(T);
    printf("\n");

    printf("pre NR order traverse:\n");
    preNROrder(T);
    printf("\n\n");

    printf("inter order traverse:\n");
    interOrder(T);
    printf("\n");

    printf("inter NR order traverse:\n");
    interNROrder(T);
    printf("\n\n");

    printf("post order traverse:\n");
    postOrder(T);
    printf("\n");

    printf("post NR order traverse:\n");
    postNROrder(T);
    printf("\n\n");

    printf("level traverse:\n");
    levelTraverse(T);
    printf("\n");

    return 0;
}

二叉树的遍历（递归与非递归）

标签：二叉树   遍历   数据结构   非递归   递归   

原文地址：http://blog.csdn.net/yangxiangyuibm/article/details/39551073