/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		Long l = new Long(-1);
		String s = Long.toHexString(l);
		System.out.println("-1 = " + s);
 
		Long aho = Long.parseLong("-ff", 16);
		System.out.println("aho = " + aho.toString());
 
		//Long rev = Long.parseLong(s, 16); // error
		Long rev = (new java.math.BigInteger(s, 16)).longValue();
		System.out.println("rev = " + rev.toString());
	}
}