Leetcode-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.

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Solution :

The Top-down solution is to check all the sub tress from the root whether

the difference of the two sub tress more than 1.

class solution {
public:
    int depth (TreeNode *root) {
        if (root == NULL) return 0;
        return max (depth(root -> left), depth (root -> right)) + 1;
    }

    bool isBalanced (TreeNode *root) {
        if (root == NULL) return true;
        
        int left=depth(root->left);
        int right=depth(root->right);
        
        return abs(left - right) <= 1 && isBalanced(root->left) && isBalanced(root->right);
    }
};