"content":"<p>Given a reference of a node in a <strong><a href=\"https://en.wikipedia.org/wiki/Connectivity_(graph_theory)#Connected_graph\" target=\"_blank\">connected</a></strong> undirected graph.</p>\n\n<p>Return a <a href=\"https://en.wikipedia.org/wiki/Object_copying#Deep_copy\" target=\"_blank\"><strong>deep copy</strong></a> (clone) of the graph.</p>\n\n<p>Each node in the graph contains a value (<code>int</code>) and a list (<code>List[Node]</code>) of its neighbors.</p>\n\n<pre>\nclass Node {\n public int val;\n public List<Node> neighbors;\n}\n</pre>\n\n<p> </p>\n\n<p><strong>Test case format:</strong></p>\n\n<p>For simplicity, each node's value is the same as the node's index (1-indexed). For example, the first node with <code>val == 1</code>, the second node with <code>val == 2</code>, and so on. The graph is represented in the test case using an adjacency list.</p>\n\n<p><b>An adjacency list</b> is a collection of unordered <b>lists</b> used to represent a finite graph. Each list describes the set of neighbors of a node in the graph.</p>\n\n<p>The given node will always be the first node with <code>val = 1</code>. You must return the <strong>copy of the given node</strong> as a reference to the cloned graph.</p>\n\n<p> </p>\n<p><strong class=\"example\">Example 1:</strong></p>\n<img alt=\"\" src=\"https://assets.leetcode.com/uploads/2019/11/04/133_clone_graph_question.png\" style=\"width: 454px; height: 500px;\" />\n<pre>\n<strong>Input:</strong> adjList = [[2,4],[1,3],[2,4],[1,3]]\n<strong>Output:</strong> [[2,4],[1,3],[2,4],[1,3]]\n<strong>Explanation:</strong> There are 4 nodes in the graph.\n1st node (val = 1)'s neighbors are 2nd node (val = 2) and 4th node (val = 4).\n2nd node (val = 2)'s neighbors are 1st node (val = 1) and 3rd node (val = 3).\n3rd node (val = 3)'s neighbors are 2nd node (val = 2) and 4th node (val = 4).\n4th node (val = 4)'s neighbors are 1st node (val = 1) and 3rd node (val = 3).\n</pre>\n\n<p><strong class=\"example\">Example 2:</strong></p>\n<img alt=\"\" src=\"https://assets.leetcode.com/uploads/2020/01/07/graph.png\" style=\"width: 163px; height: 148px;\" />\n<pre>\n<strong>Input:</strong> adjList = [[]]\n<strong>Output:</strong> [[]]\n<strong>Explanation:</strong> Note that the input contains one empty list. The graph consists of only one node with val = 1 and it does not have any neighbors.\n</pre>\n\n<p><strong class=\"example\">Example 3:</strong></p>\n\n<pre>\n<strong>Input:</strong> adjList = []\n<strong>Output:</strong> []\n<strong>Explanation:</strong> This an empty graph, it does not have any nodes.\n</pre>\n\n<p> </p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li>The number of nodes in the graph is in the range <code>[0, 100]</code>.</li>\n\t<li><code>1 <= Node.val <= 100</code></li>\n\t<li><code>Node.val</code> is unique for each node.</li>\n\t<li>There are no repeated edges and no self-loops in the graph.</li>\n\t<li>The Graph is connected and all nodes can be visited starting from the given node.</li>\n</ul>\n",
"code":"/*\n// Definition for a Node.\nclass Node {\npublic:\n int val;\n vector<Node*> neighbors;\n Node() {\n val = 0;\n neighbors = vector<Node*>();\n }\n Node(int _val) {\n val = _val;\n neighbors = vector<Node*>();\n }\n Node(int _val, vector<Node*> _neighbors) {\n val = _val;\n neighbors = _neighbors;\n }\n};\n*/\n\nclass Solution {\npublic:\n Node* cloneGraph(Node* node) {\n \n }\n};",
"__typename":"CodeSnippetNode"
},
{
"lang":"Java",
"langSlug":"java",
"code":"/*\n// Definition for a Node.\nclass Node {\n public int val;\n public List<Node> neighbors;\n public Node() {\n val = 0;\n neighbors = new ArrayList<Node>();\n }\n public Node(int _val) {\n val = _val;\n neighbors = new ArrayList<Node>();\n }\n public Node(int _val, ArrayList<Node> _neighbors) {\n val = _val;\n neighbors = _neighbors;\n }\n}\n*/\n\nclass Solution {\n public Node cloneGraph(Node node) {\n \n }\n}",
"__typename":"CodeSnippetNode"
},
{
"lang":"Python",
"langSlug":"python",
"code":"\"\"\"\n# Definition for a Node.\nclass Node(object):\n def __init__(self, val = 0, neighbors = None):\n self.val = val\n self.neighbors = neighbors if neighbors is not None else []\n\"\"\"\n\nclass Solution(object):\n def cloneGraph(self, node):\n \"\"\"\n :type node: Node\n :rtype: Node\n \"\"\"\n ",
"code":"/**\n * Definition for a Node.\n * struct Node {\n * int val;\n * int numNeighbors;\n * struct Node** neighbors;\n * };\n */\n\nstruct Node *cloneGraph(struct Node *s) {\n\t\n}",
"__typename":"CodeSnippetNode"
},
{
"lang":"C#",
"langSlug":"csharp",
"code":"/*\n// Definition for a Node.\npublic class Node {\n public int val;\n public IList<Node> neighbors;\n\n public Node() {\n val = 0;\n neighbors = new List<Node>();\n }\n\n public Node(int _val) {\n val = _val;\n neighbors = new List<Node>();\n }\n\n public Node(int _val, List<Node> _neighbors) {\n val = _val;\n neighbors = _neighbors;\n }\n}\n*/\n\npublic class Solution {\n public Node CloneGraph(Node node) {\n \n }\n}",
"envInfo":"{\"cpp\": [\"C++\", \"<p>Compiled with <code> clang 11 </code> using the latest C++ 20 standard.</p>\\r\\n\\r\\n<p>Your code is compiled with level two optimization (<code>-O2</code>). <a href=\\\"https://github.com/google/sanitizers/wiki/AddressSanitizer\\\" target=\\\"_blank\\\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\\r\\n\\r\\n<p>Most standard library headers are already included automatically for your convenience.</p>\"], \"java\": [\"Java\", \"<p><code>OpenJDK 17</code>. Java 8 features such as lambda expressions and stream API can be used. </p>\\r\\n\\r\\n<p>Most standard library headers are already included automatically for your convenience.</p>\\r\\n<p>Includes <code>Pair</code> class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.</p>\"], \"python\": [\"Python\", \"<p><code>Python 2.7.12</code>.</p>\\r\\n\\r\\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\\\"https://docs.python.org/2/library/array.html\\\" target=\\\"_blank\\\">array</a>, <a href=\\\"https://docs.python.org/2/library/bisect.html\\\" target=\\\"_blank\\\">bisect</a>, <a href=\\\"https://docs.python.org/2/library/collections.html\\\" target=\\\"_blank\\\">collections</a>. If you need more libraries, you can import it yourself.</p>\\r\\n\\r\\n<p>For Map/TreeMap data structure, you may use <a href=\\\"http://www.grantjenks.com/docs/sortedcontainers/\\\" target=\\\"_blank\\\">sortedcontainers</a> library.</p>\\r\\n\\r\\n<p>Note that Python 2.7 <a href=\\\"https://www.python.org/dev/peps/pep-0373/\\\" target=\\\"_blank\\\">will not be maintained past 2020</a>. For the latest Python, please choose Python3 instead.</p>\"], \"c\": [\"C\", \"<p>Compiled with <code>gcc 8.2</code> using the gnu11 standard.</p>\\r\\n\\r\\n<p>Your code is compiled with level one optimization (<code>-O1</code>). <a href=\\\"https://github.com/google/sanitizers/wiki/AddressSanitizer\\\" target=\\\"_blank\\\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\\r\\n\\r\\n<p>Most standard library headers are already included automatically for your convenience.</p>\\r\\n\\r\\n<p>For hash table operations, you may use <a href=\\\"https://troydhanson.github.io/uthash/\\\" target=\\\"_blank\\\">uthash</a>. \\\"uthash.h\\\" is included by default. Below are some examples:</p>\\r\\n\\r\\n<p><b>1. Adding an item to a hash.</b>\\r\\n<pre>\\r\\nstruct hash_entry {\\r\\n int id; /* we'll use this field as the key */\\r\\n char name[10];\\r\\n UT_hash_handle hh; /* makes this structure hashable */\\r\\n};\\r\\n\\r\\nstruct hash_entry *users = NULL;\\r\\n\\r\\nvoid add_user(struct hash_entry *s) {\\r\\n HASH_ADD_INT(users, id, s);\\r\\n}\\r\\n</pre>\\r\\n</p>\\r\\n\\r\\n<p><b>2. Looking up an item in a hash:</b>\\r\\n<pre>\\r\\nstruct hash_entry *find_user(int user_id) {\\r\\n struct hash_entry *s;\\r\\n HASH_FIND_INT(users, &user_id, s);\\r\\n return s;\\r\\n}\\r\\n</pre>\\r\\n</p>\\r\\n\\r\\n<p><b>3. Deleting an item in a hash:</b>\\r\\n<pre>\\r\\nvoid delete_user(struct hash_entry *user) {\\r\\n HASH_DEL(users, user); \\r\\n}\\r\\n</pre>\\r\\n</p>\"], \"csharp\": [\"C#\", \"<p><a href=\\\"https://learn.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-10\\\" target=\\\"_blank\\\">C# 10 with .NET 6 runtime</a></p>\"], \"javascript\": [\"JavaScript\", \"<p><code>Node.js 16.13.2</code>.</p>\\r\\n\\r\\n<p>Your code is run with <code>--harmony</code> flag, enabling <a href=\\\"http://node.green/\\\" target=\\\"_blank\\\">new ES6 features</a>.</p>\\r\\n\\r\\n<p><a href=\\\"https://lodash.com\\\" target=\\\"_blank\\\">lodash.js</a> library is included by default.</p>\\r\\n\\r\\n<p>For Priority Queue / Queue data structures, you may use 5.3.0 version of <a href=\\\"https://github.com/datastructures-js/priority-queue/tree/fb4fdb984834421279aeb081df7af624d17c2a03\\\" target=\\\"_blank\\\">datastructures-js/priority-queue</a> and 4.2.1 version of <a href=\\\"https://githu