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(){
	int n,A,B;
	scanf("%d%d%d",&n,&A,&B);
	if(A>B){puts("0");return 0;}
	if(n==1){printf("%d\n",A==B);return 0;}
	long long s=(n-1)*1ll*A+B,t=(n-1)*1ll*B+A;
	printf("%lld\n",t-s+1);
}