LeetCode110——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.

难度系数：

容易

实现

int getDepth(TreeNode *root)
{
    if (root == NULL) return 0;
    if (root->left == NULL && root->right == NULL)
        return 1;
    int leftd = getDepth(root->left);
    int rightd = getDepth(root->right);
    return leftd > rightd ? leftd + 1 : rightd + 1;
}

bool isBalanced(TreeNode *root) {
    if (root == NULL)
        return true;
    if (root->left == NULL && getDepth(root->right) <= 1)
        return true;
    if (root->right == NULL && getDepth(root->left) <= 1)
        return true;
    if ((getDepth(root->left) - getDepth(root->right)) > 1 || (getDepth(root->right) - getDepth(root->left)) > 1) {
        return false;
    }
    return isBalanced(root->left) && isBalanced(root->right);
}