[LeetCode] Balanced Binary Tree

[Problem]

Given a binary tree, determine if it is height-balanced.

For this problem, a height-balanced binary tree is defined as abinary tree in which the depth of the two subtrees of everynode never differ by more than 1.

[Solution]

class Solution {
public:
    bool isBalanced(TreeNode *root) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
       
        if(root == NULL)return true;
       
        // check left
        bool left = true;
        int leftH = 0;
        if(root->left != NULL){
            left = isBalanced(root->left);
            leftH = root->left->val;
        }
       
        // check right
        bool right = true;
        int rightH = 0;
        if(root->right != NULL){
            right = isBalanced(root->right);
            rightH = root->right->val;
        }
       
        // update root's height
        root->val = (leftH > rightH ? leftH : rightH) + 1;
       
        // return result
        int balance = leftH > rightH ? leftH - rightH : rightH - leftH;
        if(balance <= 1 && left == true && right == true){
            return true;
        }
        else{
            return false;
        }
    }
};

说明：版权所有，转载请注明出处。Coder007的博客