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 <cstdio>

long long N, A, B;
long long res;

int main()
{
	scanf("%lld %lld %lld", &N, &A, &B);
	res = B*(N-1)+A - (A*(N-1)+B ) + 1;
	if(res < 0)
		res = 0;
	printf("%lld\n", res);
	return 0;
}