aizlab7poprawione

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package aiz7;

/**
 *
 * @author MaxSylverWolf
 */
import java.util.*;

class Tarjan
{
    //wierzcholki
    private int V;

    private int preCount;

    private int[] low;
    //odwiedzanie
    private boolean[] visited;
    //lista utworzonego grafu
    private List<Integer>[] graph;
    //wszystkie silnie/elementy maksymalne(najwięcej połączeń)
    private List<List<Integer>> sccComp;
    private Stack<Integer> stack;

    //Silnia składowa grafu
    public List<List<Integer>> getSCComponents(List<Integer>[] graph)
    {
        V = graph.length;
        this.graph = graph;
        low = new int[V];
        visited = new boolean[V];
        stack = new Stack<Integer>();
        sccComp = new ArrayList<>();

        for (int v = 0; v < V; v++)
              if (!visited[v])
                dfs(v);

        return sccComp;
    }
    //Algorytm DFS, przeszukiwanie w głąb
    public void dfs(int v)
    {
        low[v] = preCount++;
        visited[v] = true;
        stack.push(v);
        int min = low[v];
        for (int w : graph[v])
        {
            if (!visited[w])
                dfs(w);
            if (low[w] < min)
                min = low[w];
        }
        if (min < low[v])
        {
            low[v] = min;
            return;
        }
        List<Integer> component = new ArrayList<Integer>();
        int w;
        do
        {
            w = stack.pop();
            component.add(w);
            low[w] = V;
        } while (w != v);
        sccComp.add(component);
    }

    public static void main(String[] args)
    {
        Scanner scan = new Scanner(System.in);
        System.out.println("SCC test:\n");
        System.out.println("Liczba wierzchołków: ");

        int V = scan.nextInt();

        //tworze graf
        List<Integer>[] g = new List[V];
        for (int i = 0; i < V; i++)
            g[i] = new ArrayList<Integer>();
        // krawędzie
        System.out.println("\nLiczba krawędzi");
        int E = scan.nextInt();
        //krawędzie
        System.out.println("Podaj "+ E +" x, y elementy: ");
        for (int i = 0; i < E; i++)
        {
            int x = scan.nextInt();
            int y = scan.nextInt();
            g[x].add(y);
        }

        System.out.println("Graf:");
         for (int i = 0; i < V; i++)
         System.out.println(i+"|"+g[i]);

        Tarjan t = new Tarjan();
        System.out.println("SCC : ");
        //WSZYSTKIE SCC / czyli te silnie
        List<List<Integer>> scComponents = t.getSCComponents(g);
           System.out.println(scComponents);
    }
}