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;

#define int long long

signed main() {
	int n,a,b;
	cin >> n >> a >> b;
	int ans = (n-2)*(b-a) + 1;
	int fuck = 0;
	cout << max(ans,fuck);
	return 0;
}