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) {
		// TODO 自動生成されたメソッド・スタブ
		Scanner scan = new Scanner(System.in);
		long N=scan.nextInt();
		long A=scan.nextInt();
		long B=scan.nextInt();

		long ans =B*(N-1)+A - (A*(N-1)+B) +1;
		ans = Math.max(ans, 0);
		if(N==1&&A!=B){
			ans=0;
		}
		System.out.println(ans);

	}

}
