• Question
• Solution

Question

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.

Solution

Result: Accepted Time: 8 ms

Here should be some explanations.

int depth(struct TreeNode * root)
{
    if(root == NULL)
        return 0;
    int a = depth(root->left);
    int b = depth(root->right);
    if(a-b < - 1 || a - b > 1)
        return 0x0fffffff;
    return (a>b?a:b) + 1;
}
bool isBalanced(struct TreeNode* root) {
    return depth(root) < 0x0fffffff;
}

Complexity Analytics

• Time Complexity: $O(n)$
• Space Complexity: $O(1)$