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;
  	cin >> n >> a >> b;
	if( a>b || n==1 && a!=b) {
    	cout << 0 << endl;
      	return 0; 
    }
	cout << (n-2)*(b-a)+1 <<endl;
}
