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 n,a,b; cin>>n>>a>>b;
  long long min_v=a*(n-1)+b;
  long long max_v=b*(n-1)+a;
  cout<<(max_v-min_v+1>=0 ? max_v-min_v+1:0)<<endl;
}