110.cpp

// 110. Balanced Binary Tree - https://leetcode.com/problems/balanced-binary-tree

#include <bits/stdc++.h>

using namespace std;

// Definition for a binary tree node.
struct TreeNode {
    int val;
    TreeNode *left;
    TreeNode *right;
    TreeNode(int x) : val(x), left(NULL), right(NULL) {}
};

class Solution {
public:
    int height(TreeNode* root) {
        if (root == nullptr) { return 0; }
        int left_height = height(root->left);
        if (left_height == -1) { return -1; }
        int right_height = height(root->right);
        if (right_height == -1) { return -1; }
        if (abs(left_height - right_height) > 1) return -1;
        return max(left_height, right_height) + 1;
    }

    bool isBalanced(TreeNode* root) {
        return height(root) != -1;
    }
};

int main() {
    ios::sync_with_stdio(false);

    return 0;
}