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feat: add solutions to lc problem: No.0429. N-ary Tree Level Order Traversal
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‎solution/0400-0499/0429.N-ary Tree Level Order Traversal/README.md

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@@ -44,22 +44,112 @@
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<!-- 这里可写通用的实现逻辑 -->
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“BFS 层次遍历实现”。
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<!-- tabs:start -->
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### **Python3**
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<!-- 这里可写当前语言的特殊实现逻辑 -->
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```python
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"""
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# Definition for a Node.
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class Node:
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def __init__(self, val=None, children=None):
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self.val = val
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self.children = children
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"""
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class Solution:
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def levelOrder(self, root: 'Node') -> List[List[int]]:
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if root is None:
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return []
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q = collections.deque([root])
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res = []
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while q:
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n = len(q)
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t = []
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for _ in range(n):
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node = q.popleft()
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t.append(node.val)
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if node.children:
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q.extend(node.children)
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res.append(t)
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return res
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```
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### **Java**
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<!-- 这里可写当前语言的特殊实现逻辑 -->
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```java
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/*
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// Definition for a Node.
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class Node {
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public int val;
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public List<Node> children;
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public Node() {}
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public Node(int _val) {
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val = _val;
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}
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public Node(int _val, List<Node> _children) {
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val = _val;
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children = _children;
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}
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};
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*/
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class Solution {
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public List<List<Integer>> levelOrder(Node root) {
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if (root == null) {
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return Collections.emptyList();
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}
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Deque<Node> q = new ArrayDeque<>();
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List<List<Integer>> res = new ArrayList<>();
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q.offer(root);
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while (!q.isEmpty()) {
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List<Integer> t = new ArrayList<>();
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for (int i = 0, n = q.size(); i < n; ++i) {
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Node node = q.poll();
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t.add(node.val);
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if (node.children != null) {
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q.addAll(node.children);
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}
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}
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res.add(t);
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}
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return res;
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}
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}
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```
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也可以使用 DFS:
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```java
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class Solution {
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public List<List<Integer>> levelOrder(Node root) {
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List<List<Integer>> res = new ArrayList<>();
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dfs(root, 0, res);
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return res;
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}
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private void dfs(Node root, int level, List<List<Integer>> res) {
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if (root == null) {
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return;
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}
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if (res.size() <= level) {
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res.add(new ArrayList<>());
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}
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res.get(level++).add(root.val);
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for (Node child : root.children) {
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dfs(child, level, res);
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}
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}
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}
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```
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### **...**

‎solution/0400-0499/0429.N-ary Tree Level Order Traversal/README_EN.md

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@@ -46,13 +46,76 @@
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### **Python3**
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```python
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"""
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# Definition for a Node.
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class Node:
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def __init__(self, val=None, children=None):
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self.val = val
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self.children = children
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"""
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class Solution:
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def levelOrder(self, root: 'Node') -> List[List[int]]:
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if root is None:
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return []
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q = collections.deque([root])
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res = []
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while q:
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n = len(q)
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t = []
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for _ in range(n):
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node = q.popleft()
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t.append(node.val)
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if node.children:
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q.extend(node.children)
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res.append(t)
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return res
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```
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### **Java**
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```java
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/*
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// Definition for a Node.
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class Node {
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public int val;
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public List<Node> children;
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public Node() {}
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public Node(int _val) {
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val = _val;
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}
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public Node(int _val, List<Node> _children) {
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val = _val;
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children = _children;
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}
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};
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*/
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class Solution {
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public List<List<Integer>> levelOrder(Node root) {
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if (root == null) {
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return Collections.emptyList();
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}
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Deque<Node> q = new ArrayDeque<>();
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List<List<Integer>> res = new ArrayList<>();
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q.offer(root);
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while (!q.isEmpty()) {
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List<Integer> t = new ArrayList<>();
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for (int i = 0, n = q.size(); i < n; ++i) {
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Node node = q.poll();
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t.add(node.val);
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if (node.children != null) {
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q.addAll(node.children);
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}
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}
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res.add(t);
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}
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return res;
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}
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}
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```
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### **...**

‎solution/0400-0499/0429.N-ary Tree Level Order Traversal/Solution.py

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"""
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# Definition for a Node.
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class Node:
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def __init__(self, val=None, children=None):
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self.val = val
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self.children = children
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"""
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class Solution:
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def levelOrder(self, root: 'Node') -> List[List[int]]:
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if root is None:
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return []
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q = collections.deque([root])
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res = []
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while q:
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n = len(q)
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t = []
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for _ in range(n):
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node = q.popleft()
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t.append(node.val)
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if node.children:
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q.extend(node.children)
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res.append(t)
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return res

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