import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.StringTokenizer;
public class Main {
public static void main(String[] agrs) throws Exception {
BufferedReader bf = new BufferedReader(new InputStreamReader(System.in));
String inputValues = bf.readLine();
StringTokenizer st = new StringTokenizer(inputValues);
int a = Integer.parseInt(st.nextToken());
int b = Integer.parseInt(st.nextToken());
System.out.println(a-b);
}
}