#include<stdio.h>
#include<malloc.h>
#define MaxSize 100
typedef char ElemType;
typedef struct node
{
ElemType data;
struct node *lchild;
struct node *rchild;
}BTNode;
void CreateBTNode(BTNode *&b,char *str)
{
BTNode *St[MaxSize],*p=NULL;
int top=-1,k,j=0;
char ch;
b=NULL;
ch=str[j];
while(ch!='\0')
{
switch(ch)
{
case'(':top++;St[top]=p;k=1;break;
case')':top--;break;
case',':k=2;break;
default:p=p=(BTNode * )malloc(sizeof(BTNode));
p->data=ch;p->lchild=p->rchild=NULL;
if(b==NULL)
b=p;
else
{
switch(k)
{
case 1:St[top]->lchild=p;break;
case 2:St[top]->rchild=p;break;
}
}
}
j++;
ch=str[j];
}
}
void DispBTNode(BTNode *b)
{
if(b!=NULL)
{
printf("%c",b->data);
if(b->lchild!=NULL||b->rchild!=NULL)
{
printf("(");
DispBTNode(b->lchild);
if(b->rchild!=NULL)
printf(",");
DispBTNode(b->rchild);
printf(")");
}
}
}
extern void CreateBTNode(BTNode *&b,char *str);
extern void DispBTNode(BTNode *b);
void PreOrder(BTNode *b)
{
if(b!=NULL)
{
printf("%c",b->data);
PreOrder(b->lchild);
PreOrder(b->rchild);
}
}
void PreOrder1(BTNode *b)
{
BTNode *St[MaxSize],*p;
int top=-1;
if(b!=NULL)
{
top++;
St[top]=b;
while(top>-1)
{
p=St[top];
top--;
printf("%c",p->data);
if(p->rchild!=NULL)
{
top++;
St[top]=p->rchild;
}
if(p->lchild!=NULL)
{
top++;
St[top]=p->lchild;
}
}
printf("\n");
}
}
void InOrder(BTNode *b)
{
if(b!=NULL)
{
InOrder(b->lchild);
printf("%c",b->data);
InOrder(b->rchild);
}
}
void InOrder1(BTNode *b)
{
BTNode *St[MaxSize],*p;
int top=-1;
if(b!=NULL)
{
p=b;
while(top>-1||p!=NULL)
{
while(p!=NULL)
{
top++;
St[top]=p;
p=p->lchild;
}
if(top>-1)
{
p=St[top];
top--;
printf("%c",p->data);
p=p->rchild;
}
}
printf("\n");
}
}
void PostOrder(BTNode *b)
{
if(b!=NULL)
{
PostOrder(b->lchild);
PostOrder(b->rchild);
printf("%c",b->data);
}
}
void PostOrder1(BTNode *b)
{
BTNode *St[MaxSize];
BTNode *p;
int flag,top=-1;
if(b!=NULL)
{
do
{
while(b!=NULL)
{
top++;
St[top]=b;
b=b->lchild;
}
p=NULL;
flag=1;
while(top!=-1&&flag)
{
b=St[top];
if(b->rchild==p)
{
printf("%c",b->data);
top--;
p=b;
}
else
{
b=b->rchild;
flag=0;
}
}
}
while(top!=-1);
printf("\n");
}
}
void TravLevel(BTNode *b)
{
BTNode *Qu[MaxSize];
int front,rear;
front=rear=0;
if(b!=NULL)
printf("%c",b->data);
rear++;
Qu[rear]=b;
while(rear!=front)
{
front=(front+1)%MaxSize;
b=Qu[front];
if(b->lchild!=NULL)
{
printf("%c",b->lchild->data);
rear=(rear+1)%MaxSize;
Qu[rear]=b->lchild;
}
if(b->rchild!=NULL)
{
printf("%c",b->rchild->data);
rear=(rear+1)%MaxSize;
Qu[rear]=b->rchild;
}
}
printf("\n");
}
void main()
{
BTNode *b;
CreateBTNode(b,"A(B(D,E(H(J,K(L,M(,N))))),C(F,G(,I)))");
printf("二叉树b:");DispBTNode(b);printf("\n\n");
printf("层次遍历序列:");
TravLevel(b);
printf("\n");
printf("先序遍历序列:\n");
printf("递归算法:");PreOrder(b);printf("\n");
printf("非递归算法:");PreOrder1(b);printf("\n");
printf("先序遍历序列:\n");
printf("递归算法:");InOrder(b);printf("\n");
printf("非递归算法:");InOrder1(b);printf("\n");
printf("后续遍历算法:\n");
printf("递归算法:");PostOrder(b);printf("\n");
printf("非递归算法:");PostOrder1(b);printf("\n");
}
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