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>

int main()
{
	long N, A, B;
	std::cin >> N >> A >> B;
	std::cout <<  std::max( (long)0, ( A + B * ( N - 1 ) ) - ( A * ( N - 1 ) + B ) + 1 ) << std::endl;

	return 0;
}