import java.util.ArrayList;
import java.util.List;
import java.util.Optional;
import java.lang.String;
import java.util.stream.Stream;
import java.util.function.Function;
import java.util.function.Predicate;
import java.lang.Integer;

class BugXXX {
    public main() {
        List<Integer> i = new ArrayList<>(List.of(1,2,3,4,5,6,7,8,9,10));
        Optional<Integer> tmp = i.stream().filter(x -> x == 5).map(x -> x*2).findFirst();
        return tmp;
    }
}