先序遍历非递归算法

#define maxsize 100

typedef struct

{

Bitree Elem[maxsize];

int top;

}SqStack;

void PreOrderUnrec(Bitree t)

{

    SqStack s;

    StackInit(s);

    p=t;

    while (p!=null || !StackEmpty(s))

    {

        while (p!=null)            //遍历左子树

        {

            visite(p->data);

            push(s,p);

            p=p->lchild;

        }//endwhile



        if (!StackEmpty(s))        //通过下一次循环中的内嵌while实现右子树遍历

        {

            p=pop(s);

            p=p->rchild;

        }//endif

    }//endwhile

}//PreOrderUnrec