普通二叉树转换成搜索二叉树

struct ListNode

{

    int data;

    ListNode *lchild,*rchild;

};

 

void CreateBSTree(ListNode *B2_root,ListNode *BSTree_root)

{

     if(BSTree_root==NULL)

     {

         BSTree_root = (ListNode*)malloc(sizeof(ListNode));

         BSTree_root->lchild=BSTree_root->rchild=NULL;

         BSTree_root->data=B2_root->data;

         return ;

     }

     if(B2_root->data<BSTree_root->data) CreateBSTree(B2_root,BSTree_root->lchild);

     if(B2_root->data>BSTree_root->data) CreateBSTree(B2_root,BSTree_root->rchild);

}

 

void PreOrder(ListNode *B2_root,ListNode *BSTree_root)

{

     if(B2_root==NULL) return ;//根节点就为空

     CreateBSTree(B2_root,BSTree_root);

     if(B2_root->lchild!=NULL) PreOrder(B2_root->lchild,BSTree_root);

     if(B2_root->rchild!=NULL) PreOrder(B2_root->rchild,BSTree_root);

}

 

ListNode* CreateBSTree(ListNode* B2_root)

{

    ListNode* BSTree_root=NULL;

    PreOrder(B2_root,BSTree_root);

    return BSTree_root;

}