872. Leaf-Similar 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 {
private:
    void dfs(TreeNode* root, vector<int>&v)
    {
        if(root == NULL){
            return;
        }
        if(root -> left == NULL && root -> right == NULL){
            v.push_back(root -> val);
            return;
        }

        dfs(root -> left, v);
        dfs(root -> right, v);
    }
public:
    bool leafSimilar(TreeNode* root1, TreeNode* root2) {
        vector<int> l1, l2;

        dfs(root1, l1);
        dfs(root2, l2);
        
        return l1 == l2;
    }
};