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>
#include <algorithm>
typedef long long int64;

int n, a, b;

int main()
{
    scanf("%d%d%d", &n, &a, &b);
    printf("%lld\n", std::max(0LL, (int64)(n - 2) * (b - a) + 1));
    return 0;
}
