589. N 叉樹的前序遍歷

AC Code

遞歸遍歷

class Solution {
public:vector<int> res;void dfs(Node* root){if(!root) return ;res.emplace_back(root->val);for(Node* item : root->children){dfs(item);}}vector<int> preorder(Node* root) {dfs(root);return res;}
};