import java.io.*; import java.util.*; import java.text.*; import java.math.*; import java.util.regex.*; public class Solution { static long countArray(long n, long k, long x) { // Return the number of ways to fill in the array. return (k-1)*(n-2)- n+3; } public static void main(String[] args) { Scanner in = new Scanner(System.in); int n = in.nextInt(); int k = in.nextInt(); int x = in.nextInt(); long answer = countArray(n, k, x); System.out.println(answer); in.close(); } }