import java.util.Scanner;

public class JAVA 

{

static Scanner keyboard=new Scanner(System.in);

public static void main(String args[]) 

{

long HashmentSoldier,opponentSoldier,d=0L;

while(keyboard.hasNext())

{

HashmentSoldier=keyboard.nextLong();

opponentSoldier=keyboard.nextLong();

d=opponentSoldier-HashmentSoldier;

System.out.println(Math.abs(d));

}

}

}