#include <math.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <limits.h>
#include <stdbool.h>
long int fact(int n)
{
    if(n <= 0)
        return 1; 
    
        return n*fact(n - 1);
}
long int countArray(int n, int k, int x) {
    // Return the number of ways to fill in the array.
    n = n - 2;
    if(n==k)
        return 1;
    return (k * fact(k - 1))/fact(k - 1) * fact(k - 2);
    
}

int main() {
    int n; 
    int k; 
    int x; 
    scanf("%i %i %i", &n, &k, &x);
    long int answer = countArray(n, k, x);
    printf("%ld\n", answer);
    return 0;
}