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32 | /**
* Definition for a binary tree node.
* struct TreeNode {
* int val;
* TreeNode *left;
* TreeNode *right;
* TreeNode() : val(0), left(nullptr), right(nullptr) {}
* TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
* TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left),
* right(right) {}
* };
*/
class Solution {
private:
bool _isBalanced;
int dfs(TreeNode *node) {
if (!node)
return 0;
int leftHeight = dfs(node->left);
int rightHeight = dfs(node->right);
if (std::abs(leftHeight - rightHeight) > 1)
_isBalanced = false;
return std::max(leftHeight, rightHeight) + 1;
}
public:
bool isBalanced(TreeNode *root) {
_isBalanced = true;
dfs(root);
return _isBalanced;
}
};
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