文档介绍:本贴给出二叉树先序、中序、后序三种遍历的非递归算法,此三个算法可视为标准算法。#definemaxsize100typedefstruct{  BitreeElem[maxsize];  inttop;}SqStack;voidPreOrderUnrec(Bitreet){  SqStacks;  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  }//#definemaxsize100typedefstruct{  BitreeElem[maxsize];  inttop;}SqStack;voidInOrderUnrec(Bitreet){  SqStacks;  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}//#definemaxsize100typedefenum{L,R}tagtype;typedefstruct{  Bitreeptr;  tagtypetag;}stacknode;typedefstruct{  stacknodeElem[maxsize];  inttop;}SqStack;voidPostOrderUnrec(Bitreet){  SqStacks;