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.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

/**
 *
 * @author 97797
 */
public class Main {
    public static void main(String[] args) throws IOException {

          System.out.println(new Main().run(args, System.in));
    }
    public String run(String[] args, InputStream in) throws IOException {
        BufferedReader reader = new BufferedReader(new InputStreamReader(in));
        String[] val = reader.readLine().replaceAll("\\s+", " ").split(" ");

       long N = Long.parseLong(val[0]);
       long A = Long.parseLong(val[1]);
       long B = Long.parseLong(val[2]);        
                        
        String rtn = null;

        if (A == B) {
            rtn = "1";
        } else if (A > B) {
            rtn = "0";
        } else if (N == 1) {
            rtn = "0";
        } else if (N == 2) {
            rtn = "1";
        } else {
            long c = (N-2)*(B-A) + 1;
            rtn = String.valueOf(c);
        }        
 
        return rtn;
    }        

}
