import java.util.concurrent.*;
class Summation implements Callable<Integer>
{
	private int upper;
	public Summation(int upper) {
		this.upper = upper;
	}
/* The thread will execute in this method */
	public Integer call() {
		int sum = 0;
		for (int i = 1; i <= upper; i++) {
			sum += i;
			System.out.println ("upper="+upper+", i:"+i);
		}
		return  sum;
	}
}

public class ThreadDriver
{
	public static void main(String[] args) {
		int upper = Integer.parseInt(args[0]);
		ExecutorService pool = Executors.newSingleThreadExecutor();
		Future<Integer> result = pool.submit(new Summation(upper));
		Future<Integer> result1 = pool.submit(new Summation(upper*2));

		try {
			System.out.println("sum = " + result.get());
			System.out.println("sum1 = " + result1.get());
		} catch (InterruptedException | ExecutionException ie) { }
	}
}