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.*;
import java.io.*;
 
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long N = sc.nextInt();
        long a = sc.nextInt();
        long b = sc.nextInt();
        
        long min = a*(N-1)+b;
        long max = a+b*(N-1);
        if(a>b || (N==1 && a<b)) System.out.println(0);
        else System.out.println(max-min+1);
    }
}