import java.util.concurrent.atomic.AtomicInteger;
import java.util.stream.Stream;

public class JI9029413 {

	public static void main(String[] args) {
		AtomicInteger peeks = new AtomicInteger(); 
		Stream.of(1) 
		.flatMap(n -> Stream.of(n, n + 1)) 
		.peek(n -> peeks.incrementAndGet()) 
		.findAny(); 
		assert(1 == peeks.get()); // FAILS! 

	}

}