N-ary tree traversal

This is because there are many children, so it is traversed to the level of the
N-ary tree.

class Solution {
    
    
public:
    vector<vector<int>> levelOrder(Node* root) {
    
    
      queue<Node*>que;
      if(root!=NULL) que.push(root);
      vector<vector<int>>res;
      while(que.size()>0)
      {
    
    
         vector<int>ans;
          int s=que.size();
          for(int i=0;i<s;i++)
          {
    
    
              Node *node=que.front();
              que.pop();
              ans.push_back(node->val);
              for(int i=0;i< node->children.size();i++)//每一个节点孩子的个数{
    
    
              if(node->children[i]) que.push(node->children[i]);
              }
             
          }
          res.push_back(ans);
      }
      return res;
    }
};