import java.util.ArrayList;
import java.util.List;
import org.checkerframework.checker.nullness.qual.NonNull;
class MyTop {
List<String> children = new ArrayList<String>();
}
abstract class PptRelationMin {
abstract MyTop getPpt();
void init_hierarchy_new() {
MyTop ppt = getPpt();
@NonNull Object o1 = ppt.children;
for (String rel : ppt.children) ;
@NonNull Object o2 = ppt.children;
}
}