leetcode 1305) All Elements in Two Binary Search Trees

LV. Medium 🧐

https://leetcode.com/problems/all-elements-in-two-binary-search-trees/

All Elements in Two Binary Search Trees - LeetCode

 

문제

Given two binary search trees root1 and root2, return a list containing all the integers from both trees sorted in ascending order.

 

Example 1:

Input: root1 = [2,1,4], root2 = [1,0,3]
Output: [0,1,1,2,3,4]

Example 2:

Input: root1 = [1,null,8], root2 = [8,1]
Output: [1,1,8,8]

 

Constraints:

• The number of nodes in each tree is in the range [0, 5000].
• -10^5 <= Node.val <= 10^5

 

문제 해결법

vector<int> ans에 노드 1, 노드 2를 다 돌며 val 값을 저장한다.

그 후 sort를 하고 return 하면 끝!

 

해결 코드

class Solution {
private:
	vector<int> ans;
public:
	vector<int> getAllElements(TreeNode* root1, TreeNode* root2) {
		set_ans(root1);
		set_ans(root2);
		sort(ans.begin(), ans.end());
		return ans;
	}
	void set_ans(TreeNode* root) {
		if (!root)
			return ;
		ans.push_back(root->val);
		set_ans(root->left);
		set_ans(root->right);
	}
};