[leetcode]Balanced Binary Tree

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;

}
};