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 sc = new Scanner(System.in);

		long n = sc.nextLong();
		long a = sc.nextLong();
		long b = sc.nextLong();

		long min = a * (n - 1) + b;
		long max = b * (n - 1) + a;

		long ans = 0;

		if (a == b || n == 2) {
			ans = 1;
		} else if (a > b || n == 1) {
		} else {
			ans = max - min + 1;
		}
		System.out.println(ans);

	}

}
