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.nextInt();
		long A = sc.nextInt();
		long B = sc.nextInt();
		sc.close();
		if(N == 1) {
			if(A != B) {
				System.out.println(0);
			}else {
				System.out.println(1);
			}
			System.exit(0);
		}
		if(B < A) {
			System.out.println(0);
			System.exit(0);
		}
		long min = A + B + A * (N - 2);
		long max = A + B + B * (N - 2);
		System.out.println(max - min + 1);
	}
}
