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 long a,b,c;
	cin>>a>>b>>c;
	if(b>c || c-b>a){
		cout<<0;
		return 0;
	}
	cout<<(a-1)*c+b-(c+(a-1)*b)+1;
}