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
#include<iostream>
using namespace std;
long long n,a,b;
int main()
{
	cin>>n>>a>>b;
	long long mn=a*(n-1)+b,mx=b*(n-1)+a;
	cout<<((a>b||(n==1&&a!=b))?0:mx-mn+1);
	return 0;
}