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{
  static long n, a, b;

  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);

    n = sc.nextInt();
    a = sc.nextInt();
    b = sc.nextInt();

    if(a > b || (a != b && n == 1)){
      System.out.println(0);
      return;
    }

    System.out.println(b * (n - 2) - a * (n - 2) + 1);
  }
}
