1305-all-elements-in-two-binary-search-trees.cpp

/**
 * 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 {
public:
    void inorder(TreeNode* root,vector<int> & ans){
if(root){
inorder(root->left,ans);
ans.push_back(root->val); 
    inorder(root->right,ans); 
}}
    vector<int> getAllElements(TreeNode* root1, TreeNode* root2) {
        vector<int> ans; 
        
        inorder(root1,ans); 
        inorder(root2,ans); 
        sort(ans.begin(),ans.end());
        return ans; 
        
    }
};