leetcode[110]Balanced Binary Tree

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 of every node never differ by more than 1.

/**

 * Definition for binary tree

 * struct TreeNode {

 *     int val;

 *     TreeNode *left;

 *     TreeNode *right;

 *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}

 * };

 */

class Solution {

private:

bool balance=true;

public:

int depthTree(TreeNode *root,bool &balance)

{

    if(root==NULL)return 0;

    int leftd=1+depthTree(root->left,balance);

    int rightd=1+depthTree(root->right,balance);

    if(abs(leftd-rightd)>1)balance=false;

    return leftd>rightd?leftd:rightd;

}

    bool isBalanced(TreeNode *root){

        if(root==NULL)return true;

        depthTree(root,balance);

        isBalanced(root->left);

        isBalanced(root->right);

        return balance;

    }

};