Problem:
Score : 200 points

Problem Statement

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.

Sample Input 1

4 4 6

Sample Output 1

5

There are five possible sums: 18=4+4+4+6, 19=4+4+5+6, 20=4+5+5+6, 21=4+5+6+6 and 22=4+6+6+6.

Sample Input 2

5 4 3

Sample Output 2

0

Sample Input 3

1 7 10

Sample Output 3

0

Sample Input 4

1 3 3

Sample Output 4

1

Solution in Java (OpenJDK 1.8.0) (judge verdict: Wrong Answer)

import java.util.Scanner;


public class Main
{

	public static void main(String[] args)
	{
		// TODO Auto-ge
		Scanner sc=new Scanner(System.in);
		while(sc.hasNext()){
			long x=sc.nextLong(),y=sc.nextLong(),z=sc.nextLong();
			if(y>z||x==1)System.out.println(0);
			else if(y==z)System.out.println(1);
			else System.out.println((x-2)*(z-y)+1);
		}
	}

}