import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		String N = scan.next();
		scan.close();
		int k = N.length() - 2;
		if(k > 7) {
			System.out.println(k - 8);
		}else {
			System.out.println(8 - k);
		}
	}
}