import java.util.stream.*;
import java.util.Arrays;
import java.util.Optional;

public class BigArray {

    static Optional<String>[] array;

    static void update(int i) {
	array[i] = Optional.of(Integer.toHexString(i));
    }

    public static void main(String[] args) {
	final int ARRAY_SIZE = Integer. parseInt(args[0]);
	System.out.println("\nArray size: " + ARRAY_SIZE);
	array = new Optional[ARRAY_SIZE];

	long startTime = System.nanoTime();
	for (int i = 0; i < 10; i++) {
	    IntStream.range(0, ARRAY_SIZE).parallel().forEach(BigArray::update);
	}
	long measuredTime = System.nanoTime() - startTime;
	System.out.println(measuredTime);
    }
}