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;

int main(){
  int64_t N,A,B;
  cin>>N>>A>>B;
  if(A>B)
    cout<<0<<endl;
  else
    cout<<max((B-A)*(N-2)+1,(int64_t)0)<<endl;
}