二叉树中求位于先序序列中第k个位置的结点的值,该怎么解决

二叉树中求位于先序序列中第k个位置的结点的值
编写递归算法，在二叉树中求位于先序序列中
第k个位置的结点的值。

要求实现下列函数：
TElemType PreOrder(BiTree bt, int k);
/* bt is the root node of a binary linked list, */
/* Preorder travel it and find the node whose */
/* position number is k, and return its value. */
/* if can't found it, then return '#'. */

二叉链表类型定义：
typedef struct BiTNode {
TElemType data;
BiTNode *lchild, *rchild;
} BiTNode, *BiTree;

[解决办法]

C/C++ code

 else         {             k=k-1;             if(bt->lchild)             {                                PreOrder(bt->lchild,k);             }             else if(bt->rchild)             {                                PreOrder(bt->rchild,k);             }         } 改成 else         {              if(bt->lchild)             {                                PreOrder(bt->lchild,k-1);             }             else if(bt->rchild)             {                                PreOrder(bt->rchild,k-1);             }         } 试试看
[解决办法]
把你的建树代码也发上来吧
[解决办法]
if(bt->lchild)  
           {               
               PreOrder(bt->lchild,k);  
           }  
           if(bt->rchild)  
           {               
               PreOrder(bt->rchild,k);  
           }
[解决办法]
k=k-1;  
if(bt->lchild)  
{               
 PreOrder(bt->lchild,k);  
}  
else if(bt->rchild)  
{               
 PreOrder(bt->rchild,k);  
}  
换成

m=k-1; //m为全局变量
if(bt->lchild)  
{               
 PreOrder(bt->lchild,m);  
}  
else if(bt->rchild)  
{               
 PreOrder(bt->rchild,m);  
}  

试试看
[解决办法]
探讨

if(bt->lchild) 
            {                
                PreOrder(bt->lchild,k); 
            } 
            if(bt->rchild) 
            {                
                PreOrder(bt->rchild,k); 
            } 

[解决办法]
C/C++ code
改成：else         {              if(bt->lchild)             {                                PreOrder(bt->lchild,k-1);             }             if(bt->rchild) //此处不要else            {                                PreOrder(bt->rchild,k-1);             }         }
[解决办法]
上面的好像还有点问题，再参照5楼的
k=k-1;  
if(bt->lchild)  
{               
 PreOrder(bt->lchild,k);  
}  
else if(bt->rchild)  
{               
 PreOrder(bt->rchild,k);  
}  

改为
m=k-1; //m为全局变量 
if(bt->lchild)  
{               
 PreOrder(bt->lchild,m);  
}  
if(bt->rchild) 
{               
 PreOrder(bt->rchild,m);  
}