中序遍历非递归算法

#define maxsize 100
typedef struct
{
    Bitree Elem[maxsize];
    int top;
}SqStack;

void InOrderUnrec(Bitree t)
{
    SqStack s;
    StackInit(s);
    p=t;
    while (p!=null || !StackEmpty(s))
    {
        while (p!=null)            //遍历左子树
        {
            push(s,p);
            p=p->lchild;
        }//endwhile
       
        if (!StackEmpty(s))
        {
            p=pop(s);
            visite(p->data);       //访问根结点
            p=p->rchild;           //通过下一次循环实现右子树遍历
        }//endif     
    }//endwhile
}//InOrderUnrec