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Given a reference of a node in a **connected** undirected graph.

Return a [**deep copy**](https://en.wikipedia.org/wiki/Object_copying#Deep_copy) (clone) of the graph.

Each node in the graph contains a value (`int`) and a list (`List[Node]`) of its neighbors.

```

class Node {

public int val;

public List<Node> neighbors;

}

```

**Test case format:**

For simplicity, each node's value is the same as the node's index (1-indexed). For example, the first node with `val == 1`, the second node with `val == 2`, and so on. The graph is represented in the test case using an adjacency list.

**An adjacency list** is a collection of unordered **lists** used to represent a finite graph. Each list describes the set of neighbors of a node in the graph.

The given node will always be the first node with `val = 1`. You must return the **copy of the given node** as a reference to the cloned graph.

Examples

Example 1

Input: adjList = [[2,4],[1,3],[2,4],[1,3]]

Output: [[2,4],[1,3],[2,4],[1,3]]

There are 4 nodes in the graph. 1st node (val = 1)'s neighbors are 2nd node (val = 2) and 4th node (val = 4). 2nd node (val = 2)'s neighbors are 1st node (val = 1) and 3rd node (val = 3). 3rd node (val = 3)'s neighbors are 2nd node (val = 2) and 4th node (val = 4). 4th node (val = 4)'s neighbors are 1st node (val = 1) and 3rd node (val = 3).

Example 2

Input: adjList = [[]]

Output: [[]]

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.

Example 3

Input: adjList = []

Output: []

This an empty graph, it does not have any nodes.

Constraints

•The number of nodes in the graph is in the range [0, 100].
•1 <= Node.val <= 100
•Node.val is unique for each node.
•There are no repeated edges and no self-loops in the graph.
•The Graph is connected and all nodes can be visited starting from the given node.

Code Editor

def solution():
    # Write your solution here
    pass