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.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.StringTokenizer;

public class Main {

	public static void main(String args[]) {
		FastScanner cin = new FastScanner();
		PrintWriter cout = new PrintWriter(System.out);
		solve(cin, cout);
		cout.flush();
	}

	private static void solve(FastScanner cin, PrintWriter cout) {
		assert solve(4, 4, 6) == 5;
		assert solve(5, 4, 3) == 0;
		assert solve(1, 7, 10) == 0;
		assert solve(1, 3, 3) == 1;

		long n = cin.nextInt();
		long a = cin.nextInt();
		long b = cin.nextInt();
		long ans = solve(n, a, b);
		cout.println(ans);
	}

	private static long solve(long n, long a, long b) {
		long min = a * (n - 1) + b;
		long max = b * (n - 1) + a;
		long ans = Math.max(max - min + 1, 0);
		return ans;
	}

	/**
	 * How to read input in Java — tutorial <br />
	 * By Flatfoot<br />
	 * http://codeforces.com/blog/entry/7018
	 */
	static class FastScanner {
		private BufferedReader br;
		private StringTokenizer st;

		FastScanner() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}

		String next() {
			while (st == null || !st.hasMoreElements())
				try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					throw new IllegalStateException(e);
				}
			return st.nextToken();
		}

		double nextDouble() {
			return Double.parseDouble(next());
		}

		int nextInt() {
			return Integer.parseInt(next());
		}

		String nextLine() {
			String str = "";
			try {
				str = br.readLine();
			} catch (IOException e) {
				throw new IllegalStateException(e);
			}
			return str;
		}

		long nextLong() {
			return Long.parseLong(next());
		}
	}

}
