import static org.junit.jupiter.api.Assertions.*;
import org.junit.jupiter.api.Test;
import java.util.List;
import java.util.Arrays;
import java.util.ArrayList;
public class Main {
    //Program start
    
    //Program end

    @Test
public void test1() {
    assertEquals(new ArrayList<>(Arrays.asList(2,3)), groupStrings(new ArrayList<>(Arrays.asList("a","b","ab","cde"))));
}
@Test
public void test2() {
    assertEquals(new ArrayList<>(Arrays.asList(1,3)), groupStrings(new ArrayList<>(Arrays.asList("a","ab","abc"))));
}

}