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>
 
int n,a,b;
 
int main()
{
scanf("%d%d%d",&n,&a,&b);
 
printf("%lld\n",std::max((long long)(n-2)*(b-a)+1,0ll));
 
return 0;
}