数据结构6.2

#include<stdio.h>
#include<string.h>
#include<malloc.h>//in order to include the malloc function
#include <stdlib.h>//in order to include the exit function
#define OVERFLOW 1
#define STACK_INIT_SIZE 100
#define STACKINCREMENT 10
//-----------------Binary Tree Node-----------------------
typedef struct BiTNode{        
    char name[20];
    struct BiTNode *lchild,    *rchild;
}BiTNode,*BiTree;
//-----------------Binary Tree Node------------------------------------------

//-----------------SqStack Node----------------------------------------------
typedef struct{
    BiTree *base;
    BiTree *top;
    int stacksize;
}SqStack;
//because the element in the stack is pointer,so we use the pointer of pointer
//-----------------SqStack Node----------------------------------------------

//------------------quote the functions--------------------------------------
SqStack InitStack(void);
BiTree GetTop(SqStack *);
int Push(SqStack *,BiTree );
int StackEmpty(SqStack *);
BiTree Pop(SqStack *);

int InOrder(BiTree,SqStack *);
//------------------quote the functions--------------------------------------

//-------------------------MAIN FUNCTION-------------------------------------
int main(void){
//    BiTNode a1,b1,c1,d1,e1,f1,g1;
    BiTree head,a,b,c,d,e,f,g;//a is the root
//    a=&a1;b=&b1;c=&c1;d=&d1;e=&e1;f=&f1;g=&g1;
//    head->lchild=NULL;head->rchild=a;//the head pointer point to the root
    
    head=(BiTree)malloc(sizeof(BiTNode));
    a=(BiTree)malloc(sizeof(BiTNode));
    b=(BiTree)malloc(sizeof(BiTNode));
    c=(BiTree)malloc(sizeof(BiTNode));
    d=(BiTree)malloc(sizeof(BiTNode));
    e=(BiTree)malloc(sizeof(BiTNode));
    f=(BiTree)malloc(sizeof(BiTNode));
    g=(BiTree)malloc(sizeof(BiTNode));

    strcpy(a->name,"Aname");strcpy(b->name,"Bname");strcpy(c->name,"Cname");
    strcpy(d->name,"Dname");strcpy(e->name,"Ename");strcpy(f->name,"Fname");
    strcpy(g->name,"Gname");
    a->lchild=b;a->rchild=NULL;
    b->lchild=c;b->rchild=d;
    c->lchild=NULL;c->rchild=NULL;
    d->lchild=e;d->rchild=f;
    e->lchild=NULL;e->rchild=g;
    f->lchild=NULL;f->rchild=NULL;
    g->lchild=NULL;g->rchild=NULL;    
    
    SqStack s,*sp;
    s=InitStack();
    sp=&s;

    InOrder(a,sp);
    
    return 0;
}
//-------------------------MAIN FUNCTION-------------------------------------

//---------------------------InOrderTraverse----------------------------------
int InOrder(BiTree T,SqStack *s){
    Push(s,T);//put the pointer of root in the stack    
    BiTree p;
    while(!StackEmpty(s)){
        while(p=GetTop(s)) Push(s,p->lchild);    //GetTop function returns p;go to the end in the lest diredtion        
        p=Pop(s);//in the last step above, a null pointer has been put in             
        if(!StackEmpty(s)){
            p=Pop(s);
            if(!printf("%s\n",p->name)) return 1;
            Push(s,p->rchild);
        }//if
    }//while
    return 0;    
}

//---------------------------InOrderTraverse----------------------------------

//--------------------------some execuation about the stack--------------------
SqStack InitStack(void){
    SqStack s;
    s.base=(BiTree *)malloc(STACK_INIT_SIZE*sizeof(BiTree));
    if(!s.base) exit(OVERFLOW);
    s.top=s.base;
    s.stacksize=STACK_INIT_SIZE;
    return s;
}

BiTree GetTop(SqStack *s){
    BiTree e;
//    if (s.top==s.base) return 1;
    e=*(s->top-1);
    return e;
}

int Push(SqStack *s,BiTree e){
    if(s->top-s->base>=s->stacksize){
    s->base=(BiTree *)realloc(s->base,(s->stacksize+STACKINCREMENT)*sizeof(BiTree));
        
        if(!s->base) exit(OVERFLOW);
        s->top=s->base+s->stacksize;
        s->stacksize+=STACKINCREMENT;
    }
    *s->top++ =e;
    return 0;    
}

int StackEmpty(SqStack *s){
    if(s->top==s->base) return 1;
    else return 0;
}    

BiTree Pop(SqStack *s){
    BiTree e;;
//    if(s.top=s.base) return 1;
    e=*--(s->top);
    return e;
}    
//--------------------------some execuation about the stack--------------------