树与二叉树的深度优先与广度优先算法（递归与非递归）

               

本博客前面文章已对树与二叉树有过简单的介绍，本文主要是重点介绍有关二叉树的一些具体操作与应用

阅读本文前，可以先参考本博客 各种基本算法实现小结（三）—— 树与二叉树  和  各种基本算法实现小结（二）—— 堆 栈

 

二叉树

深度层数、叶子数、节点数和广度优先算法

以及树的先序、中序、后序的递归与非递归（深度优先）

测试环境：VS2008（C）

#include "stdafx.h"#include #include #define DataType charint d_tree=0;  /* tree's depth */int l_tree=0;  /* tree's leaf */int n_tree=0;  /* tree's node *//**************************************//********     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; /* init: pn is header */ 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=pt; pn->next=qu.rear->next; qu.rear->next=pn; qu.rear=qu.rear->next;}ptree de_queue(queue &qu){ ptree pt=NULL; pnode pn=NULL; if(!empty_queue(qu)) {  pn=qu.front->next;  if(pn==qu.rear) /* qu is null: qu.front==qu.rear */   qu.rear=qu.front;  else   qu.front->next=qu.front->next->next;  pt=pn->pt;  free(pn); } return pt;}/**************************************//********     树的数据操作     ********//**************************************/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;}int depth_tree(ptree pt){ int l_len, r_len; ptree p=pt; if(p==NULL)  return 0; else {  l_len=depth_tree(p->lchild);  r_len=depth_tree(p->rchild);  return l_len>r_len?(l_len+1):(r_len+1); }}void leaf_tree(ptree pt){ ptree p=pt; if(p->lchild==NULL && p->rchild==NULL)  l_tree++; else {  leaf_tree(p->lchild);  leaf_tree(p->rchild); }}void node_tree(ptree pt){ ptree p=pt; if(p!=NULL) {  n_tree++;  node_tree(p->lchild);  node_tree(p->rchild); }}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; } }void bfs_tree(ptree pt){ ptree p=NULL; queue qu; qu=init_queue(); p=pt; if(p!=NULL) {  en_queue(qu, p);  while (!empty_queue(qu))  {   p=de_queue(qu);   printf("%3c", p->data);   if(p->lchild!=NULL)       en_queue(qu, p->lchild);   if(p->rchild!=NULL)    en_queue(qu, p->rchild);  } }}int _tmain(int argc, _TCHAR* argv[]){ ptree pt=NULL; /*pt=init_tree();*/  printf("Create 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); /**********  bfs tree **********/ printf("/n/nbfs_tree:/n"); bfs_tree(pt); /********* tree operation ********/ printf("/n/ntree operation:"); d_tree=depth_tree(pt); leaf_tree(pt); node_tree(pt); printf("/ntree's depth: %d", d_tree); printf("/ntree's leaf: %d", l_tree); printf("/ntree's node: %d", n_tree); printf("/n"); return 0;}

运行结果：

   

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