import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        long A = Integer.parseInt(sc.next());
        long B = Integer.parseInt(sc.next());

        long cnt = 0;
        if (A > B) {

        } else {
            for (long i = 1; i < B; i++) {
                if (isKadomatsu(A, B, i)) cnt++;
            }
        }

//        for (long i = 0; i < 2000000000; i++) {
//            if (isKadomatsu(A, B, i)) cnt++;
//        }
        System.out.println(cnt);
    }

    private static boolean isKadomatsu(long A, long B, long C) {
//        System.out.println(A + " "  + B + " " + C);
        if (A == B || A == C || B == C) {
            return false;
        }
        List<Long> num = new ArrayList<>();
        num.add(A);
        num.add(B);
        num.add(C);

        Collections.sort(num);

        return num.get(1) == A || num.get(1) == C;
    }
}