如何使用指針連接兩個不同的節點類型（結構）？

Question

我一直想弄清楚如何使用指針連接兩個不同的結構節點。但我無法做到這一點。看到我的畫波紋管。在左邊我 有一個「treeNode」與兩個指針（下和右）。 r指針連接到一個名爲「branchNode」的不同節點，每個「treeNode」我有五個鏈接的「branchNodes」。

這是我的問題：例如，如果「branchNode」1 不存在，我就想創建一個臨時節點 來插入它。但我不知道如何使這個臨時節點 收到 「branchNode」 2.

see image here \ n請查看的內存地址我的代碼波紋管：

的main.cpp

#include "table.h" 
#include <iostream> 

int main(){ 

    Table xxx; 

    xxx.addTreeNodes(2,100); 
    xxx.addTreeNodes(3,100); 
    xxx.addTreeNodes(1,100); 

    return 0; 

table.h

#ifndef TABLE_H_ 
#define TABLE_H_ 

class Table{ 
public: 
    Table(); 
    int treeAddress(int newAddress, int dim); 
    void addTreeNodes(int pos, int value); 


private: 
    struct treeNode { 
    public: class branchNode; 
     int address; 
     treeNode* right; 
     treeNode* below; 
    }; 

    struct branchNode : public treeNode{ 
     int address; 
     int data; 
     branchNode* next; 
    }; 

    treeNode* treeCurr; 
    treeNode* treeTemp; 
    treeNode* head; 
    branchNode* branchHead; 

    int branchDim; 

}; 

#endif 

table.cpp

#include "table.h" 
#include <iostream> 
#include <stddef.h> 

Table::Table(){ 
    branchDim = 5; 
    head = NULL; 
    treeTemp = NULL; 
    treeCurr = NULL; 

    branchHead = NULL; 

} 

int Table::treeAddress(int Address, int dim){ 
    // This function is used to calculate the address 
    // of treeNodes. 
    float val = 1 + (int)((float)Address/(float)dim); 
    if (Address % dim == 0){ 
     val--; 
    } 

    return val; 
} 

void Table::addTreeNodes(int pos, int value){ 
    // This part will create one treeNode in order, if 
    // needed. Works fine, just skip this part. 
    treeNode* tn = new treeNode; 
    tn -> address = treeAddress(pos, branchDim); 

    // if the table doesn't exist. Create one treeNode 
    if (head == NULL){ 
     tn -> below = NULL; 
     tn -> right = NULL; 
     head = tn; 
    } 
    else{ 
     // insert treeNode before. 
     if(tn -> address < head -> address){ 
      tn -> below = head; 
      tn -> right = NULL; 
      head = tn; 
     } 
     else{ 
      treeCurr = head;  
      treeTemp = head; 
      while(treeCurr != NULL && treeCurr -> address < tn -> address){ 
       treeTemp = treeCurr; 
       treeCurr = treeCurr -> below; 
      } 

      // insert treeNode on tail. 
      if (treeCurr == NULL && tn -> address > treeTemp -> address){ 
       treeTemp -> below = tn; 
       tn -> below = treeCurr; 
       tn -> right = NULL; 
      } 
      else{ 
      // insert treeNode between two others nodes. 
       if (tn -> address < treeCurr -> address){ 
        treeTemp -> below = tn; 
        tn -> below = treeCurr; 
        tn -> right = NULL; 
       } 
       else{ 
        delete[] tn; 
       } 
      } 
     } 
    } 

    // This part will create one branchNode. Here is the big problem... 

    branchNode* bn = new branchNode; 
    bn -> address = pos; 

    treeCurr = head; 
    int tPos = treeAddress(pos, branchDim); 
    while(treeCurr != NULL && tPos != treeCurr -> address){ 
     treeCurr = treeCurr -> below; 
    } 
    //If the branch is empty. 
    if (treeCurr -> right == NULL){ 
     treeCurr -> right = bn; 
     bn -> next = NULL; 
     bn -> address = pos; 
    } 

    else{ 
     //Here I wanna put the branchNode before the first branchNode. 
     if (pos < (treeCurr -> right) -> address){ 
      branchHead = treeCurr -> right; // for some reason, I don't know why, 
      bn -> next = branchHead;  // I can't do that!!!!!!!!!!. 
      treeCurr -> right = bn; 
      bn -> data = value; 
     } 
    } 
} 

Answer 1

假設存在僅一個 「樹節點」 和一些 「branchNode」 爲簡單起見。按照@ Rabbid76的提示，我能夠正確指向另一種類型的節點（謝謝！）。也許還有另一種方式，但我已經很開心了。

的main.cpp

#include "table.h" 
#include <iostream> 

int main(){ 

    Table xxx; 

    xxx.addTreeNodes(5,100); 
    xxx.addTreeNodes(3,140); 
    xxx.addTreeNodes(2,20); 

    xxx.print(); 

    return 0; 
} 

table.h

#ifndef TABLE_H_ 
#define TABLE_H_ 

class Table{ 
public: 
    Table(); 
    void addTreeNodes(int pos, int value); 
    void print(); 

private: 
    struct treeNode { 
    public: class branchNode; 
     treeNode* right; 
     treeNode* below; 
    }; 

    struct branchNode : public treeNode{ 
     int address; 
     int data; 
     branchNode* next; 
    }; 

    branchNode* branchCurr; 
    treeNode* head; 
    treeNode* tn; 
}; 

#endif 

table.cpp

#include "table.h" 
#include <iostream> 
#include <stddef.h> 

Table::Table(){ 
    head = NULL; 
    branchCurr = NULL; 
    tn = new treeNode; 
} 

void Table::addTreeNodes(int pos, int value){ 

    branchNode* bn = new branchNode; 
    bn -> address = pos; 
    bn -> data = value; 

    tn -> below = NULL; 

    if (head == NULL){ 
     head = tn; 
     bn -> next = NULL; 
     tn -> right = bn; 
    }   
    else{ 
     if (pos < ((branchNode*)head -> right) -> address){ 
      branchCurr = (branchNode*)head -> right; 
      bn -> address = pos; 
      bn -> data = value; 
      tn -> right = bn; 
      bn -> next = branchCurr; 
     } 
     else{ 
      delete[] bn; 
     } 
    } 
} 

void Table::print(){ 
    branchCurr = (branchNode*)head -> right;    
    while(branchCurr != NULL){ 
     std::cout << "address: " << branchCurr -> address 
        << ", stored value: " << branchCurr -> data << std::endl; 
     branchCurr = branchCurr -> next; 
    } 
}