算法设计-先序（根）遍历二叉树

》利用栈实现

StatusPreOrderTraverse(BiTree T,Status(*Visit)(TElemType e)){//先序遍历二叉链表，每个元素调用Visit

           InitStack(S);P=T;

           while (p||StackEmpty(S)){

                   if(p){

                       Visit(p->data);                 //访问根结点    

                       push(S,p);p=p->lchild;    //根结点入栈，遍历左子树

                    }//if                                     

                   else{                                     //根结点出栈，遍历右子树

                            pop(S,p);

                            p=p->rchild;

                   }//else

            }//while

            return OK;

         }//PreOrderTraverse

》递归实现

void PreOrder(BiTree T){

     if(T){

       printf("%c",T->data);  //访问结点

       PreOrder(T->lchild);   //遍历左子树

       PreOrder(T->rchild);   //遍历右子树

    }//if

}//PreOrder