import java.util.*;

public class Test {

  public boolean contains(Object o) { return false; }

}

class SetImpl<T> extends Test implements Set<T> {

    public int size() {
        return 0;
    }

    public boolean isEmpty() {
        return false;
    }

    public Iterator<T> iterator() {
        return null;
    }

    public Object[] toArray() {
        return new Object[0];
    }

    public <T1> T1[] toArray(T1[] a) {
        return null;
    }

    public boolean add(T t) {
        return false;
    }

    public boolean remove(Object o) {
        return false;
    }

    public boolean containsAll(Collection<?> c) {
        return false;
    }

    public boolean addAll(Collection<? extends T> c) {
        return false;
    }

    public boolean retainAll(Collection<?> c) {
        return false;
    }

    public boolean removeAll(Collection<?> c) {
        return false;
    }

    public void clear() {

    }

}