非递归实现二叉树的算法

#define STACK_INIT_SIZE 100
#define STACK 10
typedef int ElemType;
#include<stdio.h>
#include<stdlib.h>
typedef struct BiNode{
ElemType data;
struct BiNode *lchild,*rchild;
}BiNode,*BiTree;
typedef struct{
ElemType *base;
ElemType *top;
int stacksize;
}SqStack;
void CreateBiTree(BiTree &T)
{
char ch;

scanf("%c",&ch);
if(ch==' ')T=NULL;
else{
if(!(T=(BiNode *)malloc(sizeof(BiNode))))
exit(-1);
T->data=ch;
CreateBiTree(T->lchild);
CreateBiTree(T->rchild);
}
}
void InitStack(SqStack &S)
{