#include<stdio.h>
#include<stdlib.h>
#include<assert.h>
typedef int BTDataType;
typedef struct BinaryTree
{
	BTDataType data;
	struct BinaryTree* left;
	struct BinaryTree* right;
}BTNode;


BTNode* CreatTree()
{
	BTNode* n1 = (BTNode*)malloc(sizeof(BTNode));
	assert(n1);
	BTNode* n2 = (BTNode*)malloc(sizeof(BTNode));
	assert(n2); 
	BTNode* n3 = (BTNode*)malloc(sizeof(BTNode));
	assert(n3);
	BTNode* n4 = (BTNode*)malloc(sizeof(BTNode));
	assert(n4);
	BTNode* n5 = (BTNode*)malloc(sizeof(BTNode));
	assert(n5);
	BTNode* n6 = (BTNode*)malloc(sizeof(BTNode));
	assert(n6);

	n1->data = 1;
	n2->data = 2;
	n3->data = 3;
	n4->data = 4;
	n5->data = 5;
	n6->data = 6;
	
	n1->left = n2;
	n1->right = n4;
	n2->left = n3;
	n2->right = NULL;
	n3->left = NULL;
	n3->right = NULL;
	n4->left = n5;
	n4->right = n6;
	n5->left = NULL;
	n5->right = NULL;
	n6->left = NULL;
	n6->right = NULL;
	return n1;

}
// ǰ 
void PreOrder(BTNode* root)
{
	if (root == NULL)
	{
		printf("NULL ");
		return;
	}
	printf("%d ", root->data);
	PreOrder(root->left);
	PreOrder(root->right);
}

// 
void InOrder(BTNode* root)
{
	if (root == NULL)
	{
		printf("NULL ");
		return;
	}
	InOrder(root->left);
	printf("%d ", root->data);
	InOrder(root->right);
}

// 
void PostOrder(BTNode* root)
{
	if (root == NULL)
	{
		printf("NULL ");
		return;
	}
	PostOrder(root->left);
	PostOrder(root->right);
	printf("%d ", root->data);
}
int TreeSize(BTNode* root)
{
	if (root == NULL)
		return 0;
	return 1 + TreeSize(root->left) + TreeSize(root->right);
}
int TreeLeafSize(BTNode* root)
{
	if (root == NULL)
		return 0;
	if (root->left == NULL && root->right == NULL)
		return 1;
	return TreeLeafSize(root->left) + TreeLeafSize(root->right);
}
int TreeHight(BTNode* root)
{
	if (root == NULL)
		return 0;
	int leftHight = TreeHight(root->left);
	int rightHight = TreeHight(root->right);
	return leftHight > rightHight ? leftHight + 1 : rightHight + 1;
}
int TreeKLevel(BTNode* root,int k)
{
	assert(k > 0);
	if (root == NULL)
		return 0;
	if (k == 1)
		return 1;
	return TreeKLevel(root->left, k - 1) + TreeKLevel(root->right, k - 1);
}
BTNode* TreeFind(BTNode* root, BTDataType x)
{
	if (root == NULL)
		return NULL;
	if (root->data == x)
		return root;
	BTNode* left = TreeFind(root->left, x);
	if (left)
		return left;
	BTNode* right = TreeFind(root->right, x);
	if (right)
		return right;
	return NULL;
}
int main()
{
	BTNode* root = CreatTree();
	//PreOrder(root);
	//printf("\n");
	//InOrder(root);
	//printf("\n");
	//PostOrder(root);
	//printf("\n");
	//int ret = TreeHight(root);
	//int ret = TreeKLevel(root, 3);
	BTNode* ret = TreeFind(root, 3);
	printf("%p\n", ret);
	return 0;
}