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.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int N, A, B;
        N = scanner.nextInt();
        A = scanner.nextInt();
        B = scanner.nextInt();
        if ( B - A < 0) { // 2 4 10 与 1 7 10 这种情况不同，在只有1节的情况下长度不能发生变化，但是在1节以上则可以
            System.out.println("0");
            return;
        }
        if (N == 1) {
            if (A == B) {
                System.out.println("1");
            } else {
                System.out.println("0");
            }
            return;
        }
        long min = 0, max = 0;
        for (int i = 0; i < N - 1; i++) {
            min += A;
            max += B;
        }
        min += B;
        max += A;
        System.out.println(max - min + 1);
    }
}