Given a Directed Graph with V vertices and E edges, Find the number of strongly connected components in the graph.
 

Example 1:

Input:

Output:
3
Explanation:

We can clearly see that there are 3 Strongly
Connected Components in the Graph

Example 2:

Input:

Output:
1
Explanation:
All of the nodes are connected to each other.
So, there's only one SCC.

Your Task:
You don't need to read input or print anything. Your task is to complete the function kosaraju() which takes the number of vertices V and adjacency list of the graph as inputs and returns an integer denoting the number of strongly connected components in the given graph.
 

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

Constraints:
1 ≤ V ≤ 5000
0 ≤ E ≤ (V*(V-1))
0 ≤ u, v ≤ N-1
Sum of E over all testcases will not exceed 25*10⁶