1 2 3 4 5 6 7 8 9 10 11 12 13 14
   | vector<int> inorderTraversal(TreeNode* root) { 		vector<int> chain = {}; 		inorderTraversalRecur(root, &chain); 		return chain; 	}
  	void inorderTraversalRecur(TreeNode* root, vector<int>* chain) { 		if (!root) { 			return; 		} 		inorderTraversalRecur(root->left, chain); 		chain->push_back(root->val); 		inorderTraversalRecur(root->right, chain); 	}
  |