import javax.imageio.*;
import java.awt.image.*;
import java.awt.event.*;
import java.awt.*;
import java.security.NoSuchAlgorithmException;
import java.security.MessageDigest;
import java.lang.management.*;
import java.lang.reflect.*;
import java.net.*;
import java.io.*;
import javax.swing.text.*;
import javax.swing.event.*;
import javax.swing.*;
import java.util.concurrent.atomic.*;
import java.util.concurrent.*;
import java.util.regex.*;
import java.util.List;
import java.util.zip.*;
import java.util.*;


public class main {
  public static void main(String[] args) throws Exception {
    print(latestInstalledJavaX());
  }

static int latestInstalledJavaX() {
  File[] files = new File(userHome(), ".javax").listFiles();
  int v = 0;
  if (files != null) for (File f : files) {
    Matcher m = Pattern.compile("x(\\d\\d\\d?)\\.jar").matcher(f.getName());
    if (m.matches())
      v = Math.max(v, Integer.parseInt(m.group(1)));
  }
  return v;
}

static void print() {
  System.out.println();
}

static void print(Object o) {
  System.out.println(o);
}

static void print(long i) {
  System.out.println(i);
}

static String _userHome;
static String userHome() {
  if (_userHome == null) {
    if (isAndroid())
      _userHome = "/storage/sdcard0/";
    else
      _userHome = System.getProperty("user.home");
    //System.out.println("userHome: " + _userHome);
  }
  return _userHome;
}


static boolean isAndroid() { return System.getProperty("java.vendor").toLowerCase().indexOf("android") >= 0; }
}