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<stdio.h>
int main(){
	long long a,a1,a2;
	scanf("%lld %lld %lld",&a,&a1,&a2);
	long long t = a1+(a-1)*a2-(a1*(a-1)+a2);
	if(t>=0){
		printf("%lld\n",t+1);
	}
	else printf("0\n");
}