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.*;
class Main{
    /*
     * 整数 -> nextInt() (遅い場合は下のni())
     * 単語 -> next()
     * 1行 -> nextLine()
     * 注意 : nextLIneをnext(),nextInt()のあとに呼び出す場合、次が改行だと改行だけ取ってしまうので注意
     */
    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(N==1){
            if(A==B) System.out.println(1);
            else System.out.println(0);
            return;
        }

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