import java.io.*;
import java.math.*;
import java.util.*;
public class Main
{
 public static void main(String args[])
 {
     //BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
     Scanner in=new Scanner(System.in);
     String s1,s2;
     s1=in.nextBigInteger();
     BigInteger b1=new BigInteger(s1);
     s2=in.nextBigInteger();
     BigInteger b2=new BigInteger(s2);
     b1=b1.subtract(b2);
     System.out.println(b1.abs());
 }
}