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;
    }
};