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 {
public:
bool isBalanced(TreeNode *root, int &depth) {
if(root == NULL) {
depth = 0;
return true;
}
int ld;
int rd;
bool isBal = isBalanced(root->left, ld) && isBalanced(root->right, rd);
depth = ld > rd ? ld + 1 : rd + 1;
return isBal && abs(ld - rd) <= 1;
}
bool isBalanced(TreeNode *root) {
int depth;
return isBalanced(root, depth);
}
};