import java.util.*;
import java.util.zip.*;
import java.util.List;
import java.util.regex.*;
import java.util.concurrent.*;
import java.util.concurrent.atomic.*;
import java.util.concurrent.locks.*;
import java.util.function.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.text.*;
import javax.swing.table.*;
import java.io.*;
import java.net.*;
import java.lang.reflect.*;
import java.lang.ref.*;
import java.lang.management.*;
import java.security.*;
import java.security.spec.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import java.awt.geom.*;
import javax.imageio.*;
import java.math.*;
class main {
static boolean removeAll(Collection a, Collection b) {
return a != null && b != null && a.removeAll(b);
}
static void removeAll(Map a, Collection b) {
if (a != null && b != null)
for (A x : b)
a.remove(x);
}
static boolean removeAll(Collection c, B... b) {
return c != null && b != null && c.removeAll(Arrays.asList(b));
}
static void removeAll(Map a, A... b) {
if (a != null && b != null)
for (A x : b)
a.remove(x);
}}