Given an undirected graph (not necessarily connected) with V vertices and adjacency list adj. You are required to find all the vertices removing which (and edges through it) disconnects the graph into 2 or more components, or in other words, removing which increases the number of connected components.
Note: Indexing is zero-based i.e nodes numbering from (0 to V-1). There might be loops present in the graph.
Example 1:
Input:
Output:{1,4}
Explanation: Removing the vertex 1 will
discconect the graph as-
Removing the vertex 4 will disconnect the
graph as-

Your Task:
You don't need to read or print anything. Your task is to complete the function articulationPoints() which takes V and adj as input parameters and returns a list containing all the vertices removing which turn the graph into two or more disconnected components in sorted order. If there are no such vertices then returns a list containing -1.

Expected Time Complexity: O(V + E)
Expected Auxiliary Space: O(V)

Constraints:
1 ≤ V ≤ 10^{4}

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