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;

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();

		if(A>B) {
			System.out.println(0);
		}
		else if(N==1 && A!=B){
			System.out.println(0);
		}
		else if(N==1 && A==B) {
			System.out.println(1);
		}
		else {
			System.out.println(B*(N-2)-A*(N-2)+1);
		}
	}
}