问题描述：

Given a binary tree, determine if it is height-balanced.

For this problem, a height-balanced binary tree is defined as a binary tree in which the depth of the two subtrees ofevery node never differ by more than 1.

代码：

class Solution {  //c++
public:
	int getHigh(TreeNode * root, bool & isBalanc)
	{
		if(root->left == NULL && root->right == NULL)
			return 1;
		int lmin = 0;
		int rmin = 0;

		bool lbalence = true;
		bool rbalence = true;
		if(root->left != NULL)
			lmin = getHigh(root->left,lbalence);
		if(root->right != NULL)
			rmin = getHigh(root->right, rbalence);

		if(!lbalence || !rbalence || abs(lmin - rmin) >1)
			isBalanc = false;
		int high = 1+ ((lmin > rmin)?lmin:rmin);  //attention: should add () for ?:     i make a fault  here
		return high;
	}
	bool isBalanced(TreeNode *root) {
		if (root == NULL)
			return true;
        		
		bool isBalanc = true;
		getHigh(root, isBalanc);		

		return isBalanc;

	}
};

[leetcode]Balanced Binary Tree