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<cstdio>
int main(){
	int n,a,b;
	scanf("%d%d%d",&n,&a,&b);
	if(a>b||(n==1&&a!=b))printf("0\n");
	else if(a==b)printf("1\n");
	else printf("%lld\n",(1ll*b*(n-1)+a)-(1ll*a*(n-1)+b)+1);
	return 0;
}
