/************************************************************************/
/*  树
      课程要求：完成树的基本操作
      1. 树的创建和销毁
      2. 树中节点的搜索
      3. 树中节点的添加与删除
      4. 树中节点的遍历
      
      BOOL CreateTree(Tree **pTree, Node *pRoot);//Tree **pTree 树,Node *pRoot 根节点                    //创建树
      void DestroyTree(Tree *pTree);                                        //销毁树
      Node *SearchNode(Tree *pTree, int nodeIndex); //int nodeIndex数组的下标                        //根据索引寻找节点
      BOOL AddNode(Tree *pTree, int nodeIndex, int direction, Node *pNode);//int direction添加到左边还是右边   Node *pNode添加的节点      //添加节点
      BOOL DeleteNode(Tree *pTree, int nodeIndex, Node *pNode); //int nodeIndex从哪个节点删除            //删除节点
      void PreorderTraversal(Tree *pTree);                                  //前(先)序遍历演示
      void InorderTraversal(Tree *pTree);                                   //中序遍历演示
      void PostorderTraversal(Tree *pTree);                                 //后序遍历演示
      void TreeTraverse(Tree *pTree);                                       //遍历
      
   

      关于数组与树之间的算法转换

       int    3 5 8 2 6 9 7     规律解析：   父亲结点下标*2+1  该结点左  

                                  父亲结点下标*2+2  该结点右
                3(0)

         5(1)            8(2)

   2(3)      6(4)   9(5)       7(6)
*/
/************************************************************************/

#include <stdio.h>
#include <stdlib.h>

#define MAX_NODE 20
#define LEFT  1
#define RIGHT 2
#define FALSE 0
#define TRUE  1
#define BOOL int

typedef struct tag_node
{
   int data;
}Node;

typedef struct tag_tree
{
   Node *root;
}Tree;

BOOL CreateTree(Tree **pTree, Node *pRoot)
{
   *pTree = (Tree *)malloc(sizeof(Tree));//树容器的大小
   if(*pTree == NULL)
   {
      return FALSE;
   }

   (*pTree)->root = (Node *)malloc(sizeof(Node) * MAX_NODE);//树容器里面的全部元素的大小
   if((*pTree)->root == NULL)//分配内存失败
   {
      free(*pTree);//释放树容器内存
      return FALSE;
   }
   for(int i = 0; i < MAX_NODE; i++)
   {
      (*pTree)->root[i].data = 0;
   }
   (*pTree)->root[0] = *pRoot;  //意思是把根节点放进树里面(*pTree)->root[0].data = pRoot->data;
   return TRUE;
}

void DestroyTree(Tree *pTree)
{
   free(pTree->root);//释放根节点
   pTree->root = NULL;
   free(pTree);//释放树容器
   pTree = NULL;
}

Node *SearchNode(Tree *pTree, int nodeIndex)
{
   if(nodeIndex < 0 || nodeIndex >= MAX_NODE)//数组的索引必须大于等于0。或者小于#define MAX_NODE 20就行
   {
      return NULL;
   }

   if(pTree->root[nodeIndex].data == 0)//如果当前节点为0
   {
      return NULL;
   }
   else
   {
      return &(pTree->root[nodeIndex]);//节点本身的地址传过去
   }
}

//BOOL SearchNode(Tree *pTree, int nodeIndex, Node *node)
//{
// if(nodeIndex < 0 || nodeIndex >= MAX_NODE)
// {
//    return FALSE;
// }
//
// if(pTree->root[nodeIndex].data == 0)
// {
//    return FALSE;
// }
// else
// {
//    node->data = pTree->root[nodeIndex].data;  //*node = pTree->root[nodeIndex];
//
//    
//    return TRUE;
// }
//}

BOOL AddNode(Tree *pTree, int nodeIndex, int direction, Node *pNode)
{
   if(nodeIndex < 0 || nodeIndex >= MAX_NODE)
   {
      return FALSE;
   }

   if(pTree->root[nodeIndex].data == 0)
   {
      return FALSE;
   }

   pTree->root[nodeIndex * 2 + direction].data = pNode->data; //pTree->root[nodeIndex * 2 + direction] = *pNode;


   return TRUE;
}

BOOL DeleteNode(Tree *pTree, int nodeIndex, Node *pNode)
{
   if(nodeIndex < 0 || nodeIndex >= MAX_NODE)
   {
      return FALSE;
   }

   if(pTree->root[nodeIndex].data == 0)
   {
      return FALSE;
   }

   *pNode = pTree->root[nodeIndex];

   pTree->root[nodeIndex].data = 0;


   
   return TRUE;
}

void TreeTraverse(Tree *pTree)
{
   for(int i = 0; i < MAX_NODE; i++)//遍历节点
   {
      printf("%d ", pTree->root[i].data);
   }
}

int main(void)
{
   Tree *pTree = NULL;
   Node node = {3};
   Node node1 = {5};
   Node node2 = {8};
   Node node3 = {2};
   Node node4 = {6};
   Node node5 = {9};
   Node node6 = {7};
   
   CreateTree(&pTree, &node);

   AddNode(pTree, 0, LEFT, &node1);

   AddNode(pTree, 0, RIGHT, &node2);

   AddNode(pTree, 1, LEFT, &node3);

   AddNode(pTree, 1, RIGHT, &node4);

   AddNode(pTree, 2, LEFT, &node5);

   AddNode(pTree, 2, RIGHT, &node6);

   TreeTraverse(pTree);

   DestroyTree(pTree);

   system("pause");
   return 0;
}