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.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Scanner;
public class Main {
	public static void main(String[] args) throws IOException {
//		BufferedReader bf = new BufferedReader(new InputStreamReader(System.in));
		Scanner sc = new Scanner(System.in);
		long n = sc.nextInt();
		long a = sc.nextInt();
		long b = sc.nextInt();
		if(a>b) {
			System.out.println(0);
			return;
		}
		if(n==1) {
			System.out.println(a==b?1:0);
			return;
		}else {
//			int l = a*(n-1)+b;
//			int r = a+b*(n-1);
//			System.out.println(r-l+1);
			System.out.println((long)((b-a)*(n-2)+1));
		}
	}
}
