Snuke has N integers. Among them, the smallest is A, and the largest is B. We are interested in the sum of those N integers. How many different possible sums there are?

Constraints

* 1 ≤ N,A,B ≤ 10^9
* A and B are integers.

Input

Input is given from Standard Input in the following format:


N A B


Output

Print the number of the different possible sums.

Examples

Input

4 4 6


Output

5


Input

5 4 3


Output

0


Input

1 7 10


Output

0


Input

1 3 3


Output

1
import java.util.*;

public class Main {

    public static void main(String[] args) {
        // write your code here
        // AGC 008 Simple Calculator
        Scanner sc = new Scanner(System.in);
        long n = sc.nextInt() - 1;
        long a = sc.nextInt();
        long b = sc.nextInt();

        if (a > b) {
            System.out.println(0);
            return;
        }
        if (n == 0 && a != b) {
            System.out.println(0);
            return;
        }

        long min = n * a + b;
        long max = a + n * b;

        System.out.println(max - min + 1);
    }
}