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.*;
public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        // 整数の入力
        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){
        System.out.println(0);
        }
      
    else if(N == 1 && A!=B){
          System.out.println(0);
        }
      else if(A==B){
       System.out.println(1);
      }
        // 出力
        else{
          System.out.println(max-min+1);
        }
    }
}