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
/*
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 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */

import java.util.*;
/**
 *
 * @author Jeel
 */
public class Main {

    /**
     * @param args the command line arguments
     */
    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&a!=b)
        {
            System.out.print("0");
            return;
        }
        else if(b<a)
        {
            System.out.print("0");
            return;
        }
        System.out.print((b*(n-1)+a)-((a*(n-1))+b)+1);
    }
    
}
