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);
		StringBuilder sb = new StringBuilder();
		int n = sc.nextInt();
		long a = sc.nextInt();
		long b = sc.nextInt();
		long ans = 0;
		if (a > b) {
		} else if (n == 1) {
			if (a == b) {
				ans = 1;
			}
		} else if (n == 2) {
			if (a <= b) {
				ans = 1;
			}
		} else {
			ans = b * (n - 2) - a * (n - 2) + 1;
		}
		System.out.println(ans);

	}
}
