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
import java.util.*;
import java.io.*;
import java.math.*;


import static java.lang.Math.*;
import static java.util.Arrays.*;
import static java.util.Collections.*;


public class Main{ 


    static long mod=1000000007;
     // static int dx[]={1,-1,0,0};
     //  static int dy[]={0,0,1,-1};
    // static int dx[]={1,-1,0,0,1,1,-1,-1};
    // static int dy[]={0,0,1,-1,1,-1,1,-1};
    // PriorityQueue<Integer> que = new PriorityQueue<Integer>(); 
    //HashMap<Integer,Integer> map = new HashMap<Integer,Integer>();


public  static void main(String[] args)   throws Exception, IOException{

    
    Reader sc = new Reader(System.in);
    PrintWriter out=new PrintWriter(System.out);

    //  int n=sc.nextInt();  
    int n=sc.nextInt();  
    // int d[]=new int[n];
    // long d[]=new long[n];
    int a=sc.nextInt();  
    int b=sc.nextInt();
    long ans=0,aa=a,bb=b,nn=n;  
    if(a==b)ans=1;
    else if(a<b && n>1){     
            ans=(nn-1)*bb+aa-( (nn-1)*aa+bb )+1;
    }

    out.println(ans);
    out.flush();
}

static void rep(int x, long d){

}

static void db(Object... os){

    System.err.println(Arrays.deepToString(os));

}

static boolean validpos(int x,int y,int r, int c){
    
    return x<r && 0<=x && y<c && 0<=y;
    
}
 
static boolean bit(long x,int k){
    // weather k-th bit (from right) be one or zero
    return  ( 0 < ( (x>>k) & 1 )  )  ? true:false;
}

}


class XY {
    int x,y,d;
    XY(int x, int y, int d) {
        this.x=x;
        this.y=y;
        this.d=d;
    } 
}

class P implements Comparable<P>{
    int x,y;
    P(int x, int y) {
        this.x=x;
        this.y=y;
    } 
      
    public int compareTo(P p){
        return x - p.x;
    } 
}

class Reader
{ 
    private BufferedReader x;
    private StringTokenizer st;
    
    public Reader(InputStream in)
    {
        x = new BufferedReader(new InputStreamReader(in));
        st = null;
    }
    public String nextString() throws IOException
    {
        while( st==null || !st.hasMoreTokens() )
            st = new StringTokenizer(x.readLine());
        return st.nextToken();
    }
    public int nextInt() throws IOException
    {
        return Integer.parseInt(nextString());
    }
    public long nextLong() throws IOException
    {
        return Long.parseLong(nextString());
    }
    public double nextDouble() throws IOException
    {
        return Double.parseDouble(nextString());
    }
}

