class MyThread implements Runnable {
    private final int id;
    int start, end;

    public MyThread(int id) {
        this.id = id;
    }

    public int min(int a, int b) {
        if (a < b) {
            return a;
        } else {
            return b;
        }
    }

    @Override
    public void run() {
        start = (int)(id * Main.chunk_size);
        end = min((int)((id + 1) * Main.chunk_size), Main.N);

        System.out.println("Thread " + id + " calculeaza de la " + start + " la " + end);

        for (int i = start; i < end; i++) {
            Main.v[i] = Main.v[i] * 2;
        }
        //System.out.println("Salut de pe threadul #" + id);
    }

}

public class Main {
    static int N = 1007;
    static int nThreads = 4;
    static int v[] = new int[N];
    public static double chunk_size = (double) N / nThreads;


    public static void main(String[] args) {

        Thread[] threads = new Thread[nThreads];

        for (int i = 0; i < N; i++)
            v[i] = i;


        for (int i = 0; i < nThreads; i++) {
            threads[i] = new Thread(new MyThread(i));
            threads[i].start();
        }

        for (int i = 0; i < nThreads; i++) {
            try {
                threads[i].join();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }

        for (int i = 0; i < N; i++) {
            if (v[i] != i * 2) {
                System.out.println("Wrong answer");
                System.out.println(v[i] + " is different than " + i * 2);
                System.exit(1);
            }
        }
        System.out.println("Correct");
    }

}