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(){
  long N,A,B,ans;cin>>N>>A>>B;
  if(A>B)ans=0;
  else if(A==B)ans=1;
  else if(N==1)ans=0;
  else ans=(B-A)*(N-2)+1;
  cout<<ans<<endl;
}