各种基本算法实现小结（三）——树与二叉树

各种基本算法实现小结（三）—— 树与二叉树

（均已测试通过）

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二叉树——先序

测试环境：VC 6.0 (C)

#include <stdio.h> #include <malloc.h> #include <stdlib.h> struct _node { char data; struct _node *lchild; struct _node *rchild; }; typedef struct _node node, *pnode; pnode create_tree() { pnode pt; char data; scanf("%c", &data); getchar(); if(data==' ') pt=NULL; else { pt=(pnode)malloc(sizeof(node)); pt->data=data; pt->lchild=create_tree(); pt->rchild=create_tree(); } return(pt); } void print_pretree(pnode ps) { if(ps != NULL) { printf("%3c", ps->data); print_pretree(ps->lchild); print_pretree(ps->rchild); } } void main() { pnode ps; ps=create_tree(); print_pretree(ps); printf("/n"); }

运行结果：

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二叉树——各种操作

测试环境：VC 6.0 (C)

#include <stdio.h> #include <malloc.h> struct _node { char data; struct _node *lchild; struct _node *rchild; }; typedef struct _node node, *pnode; int count_l=0; /* count leaf */ int count_n=0; /* count node */ pnode create_tree() { pnode pt; char data; scanf("%c", &data); getchar(); if(data==' ') pt=NULL; else { pt=(pnode)malloc(sizeof(node)); pt->data=data; pt->lchild=create_tree(); pt->rchild=create_tree(); } return(pt); } void print_pretree(pnode ps) { if(ps != NULL) { printf("%3c", ps->data); print_pretree(ps->lchild); print_pretree(ps->rchild); } } void print_midtree(pnode ps) { if(ps != NULL) { print_midtree(ps->lchild); printf("%3c", ps->data); print_midtree(ps->rchild); } } void print_posttree(pnode ps) { if(ps != NULL) { print_posttree(ps->lchild); print_posttree(ps->rchild); printf("%3c", ps->data); } } int count_leaf(pnode ps) { if(ps != NULL) { if(ps->lchild == NULL && ps->rchild == NULL) count_l++; count_leaf(ps->lchild); count_leaf(ps->rchild); } return count_l; } int count_node(pnode ps) { if(ps != NULL) { count_n++; count_node(ps->lchild); count_node(ps->rchild); } return count_n; } int count_depth(pnode ps) { int ldep, rdep; if(ps == NULL) return 0; else { ldep=count_depth(ps->lchild); rdep=count_depth(ps->rchild); return ldep>rdep ? (ldep+1) : (rdep+1); } } void main() { pnode ps; ps=create_tree(); printf("pre order.../n"); print_pretree(ps); printf("/n"); printf("mid order.../n"); print_midtree(ps); printf("/n"); printf("post order.../n"); print_posttree(ps); printf("/n"); printf("number of leaf is: %d/n", count_leaf(ps)); printf("number of node is: %d/n", count_node(ps)); printf("max of depth is: %d/n", count_depth(ps)); }

运行结果：

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二叉树——先序、中序、后序的递归与非递归实现

测试环境：VS2008 (C)

#include "stdafx.h" #include <stdlib.h> #include <malloc.h> #define DataType char /**************************************/ /******** 树的结构定义 ********/ /**************************************/ struct _tree { DataType data; struct _tree *lchild; struct _tree *rchild; }; typedef struct _tree tree, *ptree; /**************************************/ /******** 栈的结构定义 ********/ /**************************************/ struct _node { ptree pt; struct _node *next; }; typedef struct _node node, *pnode; struct _stack { int size; pnode ptop; }; typedef struct _stack stack, *pstack; /**************************************/ /******** 堆的结构定义 ********/ /**************************************/ struct _queue { pnode front; pnode rear; }; typedef struct _queue queue, *pqueue; /**************************************/ /******** 栈的数据操作 ********/ /**************************************/ pstack init_stack() { pnode pn=NULL; pstack ps=NULL; pn=(pnode)malloc(sizeof(node)); ps=(pstack)malloc(sizeof(stack)); pn->pt=NULL; pn->next=NULL; ps->ptop=pn; return ps; } int empty_stack(pstack ps) { if(ps->ptop->next==NULL) return 1; else return 0; } void push_stack(pstack ps, ptree pt) /* flag for post tree: 0 for lchild; 1 for rchild */ { pnode pn=NULL; pn=(pnode)malloc(sizeof(node)); pn->pt=pt; pn->next=ps->ptop; ps->ptop=pn; } ptree pop_stack(pstack ps) { ptree pt=NULL; pnode pn=NULL; if(!empty_stack(ps)) { pn=ps->ptop; ps->ptop=ps->ptop->next; pt=pn->pt; free(pn); } return pt; } ptree gettop_stack(pstack ps) { if(!empty_stack(ps)) return ps->ptop->pt; } /**************************************/ /******** 堆的数据操作 ********/ /**************************************/ queue init_queue() { pnode pn=NULL; queue qu; pn=(pnode)malloc(sizeof(node)); pn->pt=NULL; pn->next=NULL; qu.front=qu.rear=pn; return qu; } int empty_queue(queue qu) { if(qu.front==qu.rear) return 1; else return 0; } void en_queue(queue qu, ptree pt) { pnode pn=NULL; pn=(pnode)malloc(sizeof(node)); pn->pt; pn->next=qu.rear->next; qu.rear=pn; } ptree de_queue(queue qu) { ptree pt=NULL; pnode pn=NULL; if(!empty_queue(qu)) { pn=qu.front; qu.front=qu.front->next; pt=pn->pt; free(pn); } return pt; } /**************************************/ /******** 堆的数据操作 ********/ /**************************************/ ptree init_tree() { ptree pt=NULL; pt=(ptree)malloc(sizeof(tree)); pt->data='0'; pt->lchild=NULL; pt->rchild=NULL; return pt; } ptree create_tree() { char ch; ptree pt=NULL; scanf("%c", &ch); getchar(); if(ch==' ') return NULL; else { pt=(ptree)malloc(sizeof(tree)); pt->data=ch; pt->lchild=create_tree(); pt->rchild=create_tree(); } return pt; } void print_pretree(ptree pt) { if(pt!=NULL) { printf("%3c", pt->data); print_pretree(pt->lchild); print_pretree(pt->rchild); } } void print_pretree2(ptree pt) { pstack ps=NULL; ptree p=NULL; ps=init_stack(); p=pt; while(p!=NULL || !empty_stack(ps)) { while(p!=NULL) { printf("%3c", p->data); push_stack(ps, p); p=p->lchild; } if(!empty_stack(ps)) { p=pop_stack(ps); p=p->rchild; } } } void print_midtree(ptree pt) { if(pt!=NULL) { print_midtree(pt->lchild); printf("%3c", pt->data); print_midtree(pt->rchild); } } void print_midtree2(ptree pt) { pstack ps=NULL; ptree p=NULL; ps=init_stack(); p=pt; while (p!=NULL || !empty_stack(ps)) { while(p!=NULL) { push_stack(ps, p); p=p->lchild; } if(!empty_stack(ps)) { p=pop_stack(ps); printf("%3c", p->data); p=p->rchild; } } } void print_posttree(ptree pt) { if(pt!=NULL) { print_posttree(pt->lchild); print_posttree(pt->rchild); printf("%3c", pt->data); } } void print_posttree2(ptree pt) { pstack ps=NULL; ptree p=NULL; ptree p2=NULL; ptree lastvisit=NULL; ps=init_stack(); p=pt; while (p!=NULL || !empty_stack(ps)) { while(p!=NULL) { push_stack(ps, p); p=p->lchild; } p2=gettop_stack(ps); /* top: rchild==null or sub_root */ if(p2->rchild==NULL || p2->rchild==lastvisit) { printf("%3c", p2->data); lastvisit=pop_stack(ps); /* pop */ } else p=p2->rchild; } } int _tmain(int argc, _TCHAR* argv[]) { ptree pt=NULL; /*pt=init_tree();*/ printf("Create recursion tree.../n"); pt=create_tree(); /************ recursion ************/ printf("/n/nrecursion..."); printf("/npre tree.../n"); print_pretree(pt); printf("/nmid tree.../n"); print_midtree(pt); printf("/npost tree.../n"); print_posttree(pt); /************ stack ************/ printf("/n/nstack, non recursion..."); printf("/npre tree.../n"); print_pretree2(pt); printf("/nmid tree.../n"); print_midtree2(pt); printf("/npost tree.../n"); print_posttree2(pt); printf("/n"); return 0; }

运行结果：

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二叉树——学习交流与修正改进

在网上看到了好多人转载这段代码，我也复制、粘贴下来学习

但在VC6.0编译器上运行并未通过，于是调试修正了几个小bug

测试运行通过后的代码粘贴如下，希望对大家学习有所帮助，谢谢！

本算法源码引用网址：http://www.ccrun.com/article.asp?i=292&d=y6y12h （二叉树实现源代码）

测试环境：VC 6.0 (C)

#include <conio.h> #include <stdio.h> #include <stdlib.h> #define OK 1 #define ERROR 0 #define TRUE 1 #define FALSE 0 #define OVERFLOW -2 typedef int status; typedef struct BiNode { char Data; struct BiNode* lChild; struct BiNode* rChild; }BiNode,*pBiNode; status CreateTree(BiNode** pTree); status PreOrderTraval(BiNode* pTree); status InOrderTraval(BiNode* pTree); status PostOrderTraval(BiNode* pTree); status Visit(char Data); status ShowLeaves(BiNode* pTree); status DelTree(BiNode* pTree); status Display(BiNode* pTree,int Level); status Clear(BiNode* pTree); BiNode *pRoot=NULL; void main() { CreateTree(&pRoot); printf("/nPreOrder:"); PreOrderTraval(pRoot); printf("/n"); printf("/nInOrder:"); InOrderTraval(pRoot); printf("/n"); printf("/nPostOrder:"); PostOrderTraval(pRoot); printf("/n"); printf("/nShowLeaves:"); ShowLeaves(pRoot); printf("/n-----------------------/n"); printf("/n"); Display(pRoot,0); printf("/n"); printf("/nDeleting Tree:/n"); DelTree(pRoot); printf("BiTree Deleted."); } status CreateTree(BiNode** pTree) { char ch; scanf("%c",&ch); getchar(); if(ch==' ') /* NOTE: enter space, example: [ab cd e ] */ { (*pTree)=NULL; } else { if(!((*pTree)=(BiNode*)malloc(sizeof(BiNode)))) { exit(OVERFLOW); } (*pTree)->Data=ch; CreateTree(&((*pTree)->lChild)); CreateTree(&((*pTree)->rChild)); } return OK; } status PreOrderTraval(BiNode* pTree) { if(pTree) { if(Visit(pTree->Data)) { if(PreOrderTraval(pTree->lChild)) { if(PreOrderTraval(pTree->rChild)) { return OK; } } } return ERROR; } else { return OK; } } status InOrderTraval(BiNode* pTree) { if(pTree) { if(InOrderTraval(pTree->lChild)) { if(Visit(pTree->Data)) { if(InOrderTraval(pTree->rChild)) { return OK; } } return ERROR; } return ERROR; } else return OK; } status PostOrderTraval(BiNode* pTree) { if(pTree) { if(PostOrderTraval(pTree->lChild)) { if(PostOrderTraval(pTree->rChild)) { if(Visit(pTree->Data)) { return OK; } return ERROR; } } return ERROR; } else { return OK; } } status Visit(char Data) { printf("%c",Data); return OK; } status Display(BiNode* pTree,int Level) { int i; if(pTree==NULL) return FALSE; Display(pTree->lChild,Level+1); for(i=0;i<Level-1;i++) { printf(" "); } if(Level>=1) { printf("--"); } printf("%c/n",pTree->Data); Display(pTree->rChild,Level+1); return TRUE; } status ShowLeaves(BiNode* pTree) { if(pTree) { if(ShowLeaves(pTree->lChild)) { if(ShowLeaves(pTree->rChild)) { if((pTree->lChild==NULL)&&(pTree->rChild==NULL)) { if(!Visit(pTree->Data)) { return ERROR; } } return OK; } } return ERROR; } else { return OK; } } status DelTree(BiNode* pTree) { if(pTree) { if(DelTree(pTree->lChild)) { if(DelTree(pTree->rChild)) { printf("Deleting %c/n",pTree->Data); free((void*)pTree); return OK; } } return ERROR; } else return OK; }

运行结果：

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上述代码改进后，逻辑更清晰

，并添加了计算二叉树层次的函数 ShowDepth(BiNode* pTree)

具体代码如下：

#include <conio.h> #include <stdio.h> #include <stdlib.h> #define OK 1 #define ERROR 0 #define TRUE 1 #define FALSE 0 #define OVERFLOW -2 typedef int status; typedef struct BiNode { char Data; struct BiNode* lChild; struct BiNode* rChild; }BiNode,*pBiNode; status CreateTree(BiNode** pTree); status PreOrderTraval(BiNode* pTree); status InOrderTraval(BiNode* pTree); status PostOrderTraval(BiNode* pTree); status Visit(char Data); status ShowLeaves(BiNode* pTree); status ShowDepth(BiNode* pTree); status DelTree(BiNode* pTree); status Display(BiNode* pTree,int Level); status Clear(BiNode* pTree); BiNode *pRoot=NULL; void main() { CreateTree(&pRoot); printf("/nPreOrder:"); PreOrderTraval(pRoot); printf("/n"); printf("/nInOrder:"); InOrderTraval(pRoot); printf("/n"); printf("/nPostOrder:"); PostOrderTraval(pRoot); printf("/n"); printf("/nShowLeaves:"); ShowLeaves(pRoot); printf("/nShowDepth:%d/n", ShowDepth(pRoot)); printf("/n------------------/n"); printf("/n"); Display(pRoot,0); printf("/n"); printf("/nDeleting Tree:/n"); DelTree(pRoot); printf("BiTree Deleted."); } status CreateTree(BiNode** pTree) { char ch; scanf("%c",&ch); getchar(); if(ch==' ') /* NOTE: enter space, example: [ab cd e ] */ (*pTree)=NULL; else { if(!((*pTree)=(BiNode*)malloc(sizeof(BiNode)))) exit(OVERFLOW); (*pTree)->Data=ch; CreateTree(&((*pTree)->lChild)); CreateTree(&((*pTree)->rChild)); } return OK; } status PreOrderTraval(BiNode* pTree) { if(pTree) { Visit(pTree->Data); PreOrderTraval(pTree->lChild); PreOrderTraval(pTree->rChild); } return OK; } status InOrderTraval(BiNode* pTree) { if(pTree) { InOrderTraval(pTree->lChild); Visit(pTree->Data); InOrderTraval(pTree->rChild); } return OK; } status PostOrderTraval(BiNode* pTree) { if(pTree) { PostOrderTraval(pTree->lChild); PostOrderTraval(pTree->rChild); Visit(pTree->Data); } return OK; } status Visit(char Data) { printf("%c",Data); return OK; } status Display(BiNode* pTree,int Level) { int i; if(pTree==NULL) return FALSE; Display(pTree->lChild,Level+1); for(i=0;i<Level-1;i++) { printf(" "); } if(Level>=1) { printf("--"); } printf("%c/n",pTree->Data); Display(pTree->rChild,Level+1); return TRUE; } status ShowLeaves(BiNode* pTree) { if(pTree) { ShowLeaves(pTree->lChild); ShowLeaves(pTree->rChild); if((pTree->lChild==NULL)&&(pTree->rChild==NULL)) Visit(pTree->Data); } return OK; } status ShowDepth(BiNode* pTree) { int ldep=0, rdep=0; if(!pTree) return 0; else { ldep=ShowDepth(pTree->lChild); rdep=ShowDepth(pTree->rChild); return ldep>rdep ? (ldep+1) : (rdep+1); } } status DelTree(BiNode* pTree) { if(pTree) { DelTree(pTree->lChild); DelTree(pTree->rChild); printf("Deleting %c/n",pTree->Data); free((void*)pTree); } return OK; }

运行结果：