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;
import java.util.stream.IntStream;

public class Main {
	static final Scanner s = new Scanner(System.in);
	static IntStream REPS(int v){
		return IntStream.range(0,v);
	}
	public static void main(String[]__){
		long n=s.nextInt(),a=s.nextInt(),b=s.nextInt();
		long v=(a+b*(n-1))-(a*(n-1)+b);
		System.out.println(v<0?0:v+1);
	}
}
