LeetCode Q110: 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.

	/**
	* 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:
	bool helper(TreeNode* node, int& height){
	if(node==NULL){
	height=0;
	return true;
	}
	bool rt=true;
	bool lt=true;
	int lheight=0;
	int rheight=0;
	if(node->left!=NULL)
	lt=helper(node->left, lheight);
	if(node->right!=NULL)
	rt=helper(node->right, rheight);
	if(lt&&rt&&abs(rheight-lheight)<=1){
	height=max(lheight, rheight)+1;
	return true;
	}
	return false;
	}
	bool isBalanced(TreeNode* root) {
	int height=0;
	bool res=helper(root, height);
	return res;
	}
	};

view raw Q110BalancedBinaryTree.cpp hosted with ❤ by GitHub