【树】leetcode_429_N 叉树的层序遍历

【树】leetcode_429_N 叉树的层序遍历

/*
// Definition for a Node.
class Node {
public:
    int val;
    vector<Node*> children;

    Node() {}

    Node(int _val) {
        val = _val;
    }

    Node(int _val, vector<Node*> _children) {
        val = _val;
        children = _children;k
    }
};
*/

class Solution {
public:
    vector<vector<int>> levelOrder(Node* root) {
        vector<vector<int>> result;
        if (root ==nullptr) return result;
        Node *cur = root;
        vector<int> layer;
        queue<Node*> q_node;

        q_node.push(root);
        while(!q_node.empty()){
            int q_size = q_node.size();
            for (int i = 0; i<q_size; i++) {
                cur = q_node.front();
                q_node.pop();
                layer.push_back(cur->val);

                for (int i = 0; i < cur->children.size(); i++){
                    q_node.push(cur->children[i]);
                }
            }
            result.push_back(layer);
            layer.clear();
        }
        return result;
    }
};