//Three.h #ifndef THREE_H #define THREE_H #include <iostream> #include <string.h> using namespace std; typedef enum{Link, Thread} Tag; typedef struct ThreeNode { char data; struct ThreeNode *lChild, *rChild, *Parent;//采用三叉链表,增加一个指向双亲的结点 Tag lTag, rTag; }ThreeNode, *PThreeNode; class Three { protected: PThreeNode root; public: Three()//默认构造函数 { root = NULL; } Three(PThreeNode r)//构造函数 { root = r; } ~Three()//析构函数 { PThreeNode temp = First(); while(temp != root) { delete temp; temp = Next(temp); } delete root; } void CreateTree(PThreeNode &e, char TreeArray[], PThreeNode Par)//已知后序序列,创建树 { static int count = strlen(TreeArray)-1;//这里我们反其道而行之,总最后一个开始,也就是根节点 char ch = TreeArray[count--];//后序遍历的第一个字符一定为‘#‘,这样程序就不对了 if(ch == ‘#‘) { e = NULL; } else { e = new ThreeNode; e->data = ch; e->Parent = Par; e->lTag = Link; e->rTag = Link; CreateTree(e->rChild, TreeArray, e); CreateTree(e->lChild, TreeArray, e); } } void CreateTree(char TreeArray[]) { CreateTree(root, TreeArray, NULL); } void Print(PThreeNode &e)//后序打印二叉树 { if(e != NULL) { Print(e->lChild); Print(e->rChild); cout << e->data << " "; } } void Print() { Print(root); } void ThreadPrint()//线索化,后序打印二叉树 { PThreeNode temp = First(); while(temp != root) { cout << temp->data << " "; temp = Next(temp); } cout << temp->data; } PThreeNode Find(const char &ch) //查找结点 { PThreeNode p = First(); while (p != NULL && p->data != ch) { p = Next(p); } return p; } PThreeNode First() const//找到后序遍历的首位置 { if (root == NULL) return NULL; else { PThreeNode p = root; while (p->lChild != NULL) p = p->lChild; return p; } } PThreeNode Next(PThreeNode &e)//返回结点的下一位置 { PThreeNode temp = e; PThreeNode Par = temp->Parent; if(temp->rTag == Thread) { return temp->rChild; } else if(Par->rChild == temp) { return Par; } else if(root == e) { return root; } else { temp = Par; while(temp->lChild != e || temp->lTag != Thread) { temp = temp->rChild; while(temp->lTag == Link) { temp = temp->lChild; } } return temp; } } PThreeNode GetRoot() const//得到根节点 { return root; } void ThreadTree(PThreeNode &e, PThreeNode &pre)//后序线索二叉树,pre用引用传递,使其能保存上次的值 { if(e !=NULL ) { ThreadTree(e->lChild, pre); ThreadTree(e->rChild, pre); if(e->lChild == NULL) { e->lChild = pre; e->lTag = Thread; } if(pre != NULL && pre->rChild == NULL) { pre->rChild = e; pre->rTag = Thread; } pre = e; } } void ThreadTree()//后序线索二叉树 { PThreeNode temp = NULL; ThreadTree(root, temp); } }; #endif
#include "Three.h" #include <iostream> using namespace std; int main() { char ch[] = {‘#‘,‘#‘,‘D‘,‘#‘,‘#‘,‘G‘,‘#‘,‘E‘,‘B‘,‘#‘,‘#‘,‘#‘,‘F‘,‘C‘,‘A‘}; Three bt; PThreeNode p; bt.CreateTree(ch); cout << "后序遍历的顺序为:"; bt.Print(); cout << endl; bt.ThreadTree(); cout << "线索化后,后序遍历的顺序为:"; bt.ThreadPrint(); cout << endl; p = bt.Find(‘A‘);//根节点为特殊情况 if(p != bt.GetRoot()) { p = bt.Next(p); cout << "该结点后继为:" << p->data << endl; } else cout << "该结点为线索树的最后一个元素,无后继!!!" << endl; system("pause"); return 0; }
用的自己借助sublime TEXT搭建的C++环境,教程在前面有,这里插个链接。
原文地址:https://www.cnblogs.com/1by1/p/10386374.html
时间: 2024-10-10 02:01:39