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[]) {

        // 入力
        Scanner sc = new Scanner(System.in);
        long n = Long.parseLong(sc.next());
        long a = Long.parseLong(sc.next());
        long b = Long.parseLong(sc.next());

        // 主処理
        long min = a * (n - 1) + b;
        long max = a + b * (n - 1);
        long result;

        if (b < a) {
            result = 0;
        } else if (n == 1) {
            result = a == b ? 1 : 0;
        } else {
            result = max - min + 1; // 重複分の数1を補正
        }

        // 出力
        System.out.println(result);
        sc.close();
    }
}