[LeetCode] 872. Leaf-Similar Trees c++

• 문제

Consider all the leaves of a binary tree, from left to right order, the values of those leaves form a leaf value sequence.

출처 : https://leetcode.com/problems/leaf-similar-trees/

For example, in the given tree above, the leaf value sequence is (6, 7, 4, 9, 8).

Two binary trees are considered leaf-similar if their leaf value sequence is the same.

Return true if and only if the two given trees with head nodes root1 and root2 are leaf-similar.

Input: root1 = [3,5,1,6,2,9,8,null,null,7,4], root2 = [3,5,1,6,7,4,2,null,null,null,null,null,null,9,8]
Output: true

 

두개의 tree가 주어지고 가장 마지막 depth 노드들의 sequence를 구하는 문제이다.

 

• 문제 해결

class Solution {
    
private:
    void dfs(TreeNode* curr, vector<int>& vec){
        
        if(!curr){
            return;
        }
        
        if( !(curr->left || curr->right)){
            vec.push_back(curr->val);
        }
        
        dfs(curr->left, vec);
        dfs(curr->right, vec);
    }
    
public:
    bool leafSimilar(TreeNode* root1, TreeNode* root2) {
        vector<int> v1;
        vector<int> v2;
        
        dfs(root1, v1);
        dfs(root2, v2);
        
        if(v1 == v2)
            return true;
        
        return false;
    }
    
};