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;

typedef long long ll;

int main()
{
  ll n, a, b;
  cin >> n >> a >> b;

  ll ans = max(0LL, (a+(n-1)*b) - ((n-1)*a+b) + 1);

  cout << ans << endl;

  return 0;
}
