输入一棵二叉树的根结点，判断该树是不是平衡二叉树。如果某二叉树中任意结点的左右子树的深度相差不超过1，那么它就是一棵平衡二叉树。例如下图中的二叉树就是一棵平衡二叉树：

// IsbalenceTree.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"
#include<iostream>
#include<algorithm>
using namespace std;

struct BiNOde
{
	char ele;
	BiNOde* lnode;
	BiNOde* rnode;
};

BiNOde*create_tree()
{
	BiNOde * root = new BiNOde;
	BiNOde*node1 = new BiNOde;
	BiNOde*node2 = new BiNOde;
	BiNOde*node3 = new BiNOde;
	BiNOde*node4 = new BiNOde;
	BiNOde*node5 = new BiNOde;
	BiNOde*node6 = new BiNOde;
	BiNOde*node7 = new BiNOde;
	BiNOde*node8 = new BiNOde;
	BiNOde*node9 = new BiNOde;
	BiNOde*node10 = new BiNOde;
	BiNOde*node11 = new BiNOde;
	root->ele = 0;
	node1->ele = 1;
	node2->ele = 2;
	node3->ele = 3;
	node4->ele = 4;
	node5->ele = 5;
	node6->ele = 6;
	node7->ele = 7;
	node8->ele = 8;
	node9->ele = 9;
	node10->ele = 10;
	node11->ele = 11;
	root->lnode = node1;
	root->rnode = node2;
	node1->lnode = node3;
	node1->rnode = node4;
	node2->lnode = node7;
	node2->rnode = node8;
	node3->lnode = node5;
	node3->rnode = node11;
	node4->lnode = node10;
	node4->rnode = NULL;
	node5->lnode = node6;
	node5->rnode = NULL;
	node6->lnode = NULL;
	node6->rnode = NULL;
	node7->lnode = node9;
	node7->rnode = NULL;
	node8->lnode = NULL;
	node8->rnode = NULL;
	node9->lnode = NULL;
	node9->rnode = NULL;
	node10->lnode = NULL;
	node10->rnode = NULL;
	node11->lnode = NULL;
	node11->rnode = NULL;
	//BiNOde*node12 = new BiNOde;
	//node12->ele = 12;
	//node12->lnode = NULL;
	//node12->rnode = NULL;
	//node6->lnode = node11;
	return root;
}

int depth(BiNOde*node)
{

	if (node == NULL || node->lnode == NULL&&node->rnode == NULL)
		return 0;
	if (node->lnode != NULL)
		if (node->rnode != NULL)
		{
		if ((node->lnode->lnode == NULL&&node->lnode->rnode == NULL
			&&node->rnode->lnode == NULL&&node->rnode->rnode == NULL))
			return 1;
		}
		else
		{
			if ((node->lnode->lnode == NULL&&node->lnode->rnode == NULL))
				return 1;
		}
	else
		if (node->rnode != NULL)
		{
		if (node->rnode->lnode == NULL&&node->rnode->rnode == NULL)
			return 1;
		}
	return 1 + max(depth(node->lnode), depth(node->rnode));

}


bool IsbalenceTree(BiNOde* node)
{
	if (node->lnode == NULL&&node->rnode == NULL)
		return true;
	if (node->lnode == NULL)
	{
		if (node->rnode->lnode != NULL || node->rnode->rnode != NULL)
			return false;
		return true;
	}
	if (node->rnode == NULL)
	{
		if (node->lnode->lnode != NULL || node->lnode->rnode != NULL)
			return false;
		return true;
	}
	if (abs(depth(node->lnode) - depth(node->rnode)) > 1)
		return false;
	return IsbalenceTree(node->lnode) && IsbalenceTree(node->rnode);

}


int _tmain(int argc, _TCHAR* argv[])
{
	//char b = 0;
	//cout << b << endl;
	BiNOde*root = new BiNOde;
	root = create_tree();

	cout << depth(root) << endl;
	if (IsbalenceTree(root))
		cout << "是平衡二叉树" << endl;
	else
		cout << "不是平衡二叉树" << endl;
	system("pause");
	return 0;
}

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