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[]srgs) {
	Scanner scan=new Scanner(System.in);
	long a=scan.nextInt();
	long b=scan.nextInt();
	long c=scan.nextInt();
	long st=1;
		if(b>c) {
			st=0;
		}
		else if(a==1&&b==c) {
			st=1;
		}
		else if(a==1) {
			st=0;
		}
		else {
			st=(c-b)*(a-2)+1;
		}
	System.out.println(st);
	}
}
