二叉树常用操作

写于2016-06-18 16:21

#include<iostream>using namespace std;struct xuqi{    string data;xuqi*L,*R;};///////////先序创建二叉树////////////// void create( xuqi *  &T ){string a;cin>>a; if(a.compare("#")==0)T=NULL; else{     T=new xuqi;        T->data=a;              create(T->L);        create(T->R);     } }  ////////////前序遍历//////////////////////////  void  preorderTraversal(xuqi  * & T)   {    if(T){cout<<"遍历到的数值为："<<T->data<<endl; preorderTraversal(T->L);   preorderTraversal(T->R);  }    }   ///////中序遍历二叉树///////////////    void inorderTraversal(xuqi  * & T)   {    if(T){inorderTraversal(T->L);   cout<<"遍历到的数值为："<<T->data<<endl;  inorderTraversal(T->R);  }    }    //////////后序遍历//////////////     void  postorderTraversal(xuqi  * & T)   {    if(T){ postorderTraversal(T->L);     postorderTraversal(T->R); cout<<"遍历到的数值为："<<T->data<<endl ;}    }   ///////////// 计算二叉树深度/////////      int  depthOfBinaryTree(  xuqi *&T) { if(T==NULL)    return 0;      int left=1;     int right=1;  left+=depthOfBinaryTree(T->L); right+=depthOfBinaryTree(T->R);  cout<<"目前left和right分别为："<<left<<"   "<<right<<endl;     if(left>right)return  left;        else return right;  }   //////////层次遍历/////////////////////////////   int levelTraverse(  xuqi *&T  ,int c)   {    if(T==NULL){   cout<<"此节点为空"<<endl;   return 0;       }    else if(c==0)      {      cout<<T->data<<"  ";  return 1;       }  return levelTraverse(T->L,c-1)+levelTraverse(T->R,c-1);   }    void  levelchange(xuqi * &T)//修改层操作      {     int i=0;    while(true)    {      if( levelTraverse(T,i++)==0)break;cout<<endl<<"第"<<i<<"层结束"<<endl;    } } int main(){   xuqi* T;   create(T); //先序 构造二叉树     cout<<"先序遍历："<<endl;    preorderTraversal(T);    cout<<"中先序遍历："<<endl;    inorderTraversal(T);   cout<<"后序遍历："<<endl;    postorderTraversal(T);   int c= depthOfBinaryTree(T);   cout<<"二叉树的深度为:"<<c<<endl;   cout<<"层次遍历:"<<endl;     levelchange(T);    return 0;    /*    测试数据:1293##10##1513##1817##21##     */ } 

上面四图为：测试数据+三序遍历+二叉树深度+层次遍历

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/*   要求：二叉树题目：根据前序和中序遍历构建二叉树*/#include<iostream> using namespace std;   struct xuqi {     char data; xuqi *  L,*R; }; //根据先中序列 构建二叉树 void CreatBiTree(xuqi * &root,string preOrder,string inOrder)  {       if(preOrder.length()==0)       {           root=NULL;//           return;       }       char first=preOrder[0];        int index=inOrder.find(first);//找到该字符在中序串中的下标        string leftChildInOrder=inOrder.substr(0,index);       string rightChildInOrder=inOrder.substr(index+1);   int leftChildLength=leftChildInOrder.length();//获取左半部分长度    int rightChildLength= rightChildInOrder.length();//获取右半部分长度   string leftChildPreOrder=preOrder.substr(1,leftChildLength);         string rightChildPreOrder=preOrder.substr(leftChildLength+1);       root=new xuqi;       root->data=first;  cout<<"  遍历到的值"<<first<<"       index："<<index<<endl;   cout<<"       leftChildInOrder and rightChildInOrder:"<<leftChildInOrder<<"   and   "<<rightChildInOrder<<endl;        cout<<"       leftChildLength  and   rightChildLength:"<<leftChildLength<<"     "<< rightChildLength<<endl;  cout<<"       leftChildPreOrder  and   rightChildPreOrder:"<<leftChildPreOrder<<"   and  "<< rightChildPreOrder<<endl;   CreatBiTree(root->L,leftChildPreOrder,leftChildInOrder);        CreatBiTree(root->R,rightChildPreOrder,rightChildInOrder);   }     ////////////前序遍历//////////////////////////  void  preorderTraversal(xuqi  *  T)     {       if(T)          {cout<<T->data;//输出遍历到的值                  preorderTraversal(T->L);            preorderTraversal(T->R);            }        }  int main() {    string preOrderStr="ABCDEFGHIJKLMN";//先序序列     string InOrderStr ="CBEDAHGJIFKMNL";//中序序列     cout<<"先序序列串为:"<<preOrderStr<<endl<<"中序序列串为:"<< InOrderStr<<endl;     //创建二叉树xuqi *root;     CreatBiTree(root,preOrderStr,InOrderStr);//构建二叉树     cout<<"先序遍历结果为："<<endl;preorderTraversal(root);//前序遍历   }