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 <bits/stdc++.h>

using namespace std;

using ll = long long;

int main() {
    ll N, A, B;cin >> N >> A >> B;
    cout<<max((B * (N - 1) + A) - (A * (N - 1) + B) + 1, 0LL)<<endl;
    return 0;
}