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 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 javax.imageio.*;
import java.math.*;
class main {

static int modBase1(int a, int b) {
  return b == 0 ? 0 : mod(a-1, b)+1;
}
// better modulo that gives positive numbers always
static int mod(int n, int m) {
  return (n % m + m) % m;
}

static long mod(long n, long m) {
  return (n % m + m) % m;
}

static BigInteger mod(BigInteger n, int m) {
  return n.mod(bigint(m));
}

static double mod(double n, double m) {
  return (n % m + m) % m;
}




static BigInteger bigint(String s) {
  return new BigInteger(s);
}

static BigInteger bigint(long l) {
  return BigInteger.valueOf(l);
}


}