StronglyConnectedComponents

import static java.util.Arrays.asList;

import java.util.*;

public class StronglyConnectedComponents {
	private void search(Set<Integer> res, Map<Integer,Set<Integer>> nodes, int cur, int start, Set<Integer> visited, Set<Integer> currVisited) {
		currVisited.add(cur);
		visited.add(cur);
		for(int next:nodes.get(cur)) {
			if(res.contains(next)&&next!=start) {
				res.remove(next);
			}
			if(!currVisited.contains(next)) {
				search(res,nodes,next,start,visited,currVisited);
			}
		}
	}
	
	public List<Integer> getMin(int[][] edges, int n){
		Map<Integer,Set<Integer>> nodes = new HashMap<>();
		for(int i = 0 ; i < edges.length ; i++) {
			nodes.put(i, new HashSet<>());
		}
		for(int[] edge:edges) {
			nodes.get(edge[0]).add(edge[1]);
		}
		Set<Integer> visited = new HashSet<>();
		Set<Integer> res = new HashSet<>();
		for(int i = 0 ; i < n ; i++) {
			if(!visited.contains(i)) {
				res.add(i);
				visited.add(i);
				search(res,nodes,i,i,visited,new HashSet<>());
			}
			
		}
		return new ArrayList<>(res);
	}

	public static void main(String[] args) {
	
		 int[][] edges = {  
				  {0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, 
				  {0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, 
				  {0, 0, 0 ,0, 0, 0, 0, 0, 0, 1}, 
				  {0, 0, 0, 1, 0, 1, 0, 1, 0, 0}, 
				  {0, 0, 0, 0, 0, 0 ,0, 0, 1, 0},
				  {0, 0, 0, 0, 0, 0, 0, 0, 1, 0}, 
				  {0, 0, 0, 0, 0, 0, 1, 0, 0 ,0}, 
				  {0, 0, 0, 0, 1, 0, 0, 0, 0, 0}, 
				  {0, 0, 0, 0, 0, 0, 0, 1, 0, 0}, 
				  {0, 0, 0, 1, 0, 0, 1, 0, 0, 0}};
				 
				 
		 edges = new int[][]{{2, 9}, {3, 3}, {3, 5}, {3, 7}, {4, 8}, {5, 8}, {6, 6}, {7, 4}, {8, 7}, {9, 3}, {9, 6}};
         
		 System.out.println(new StronglyConnectedComponents().getMin(edges, 10));
	}
}