import java.util.Scanner;
import javax.swing.RowFilter;
public class Main_1 {
/*
* 2*n皇后
*/
public static int num=0;
public static int[] row=new int[16];
public static int[][] arm=new int[8][8];
public static void queen(int i,int n) {
int j,k;
if(i==n) {
num++;
// for (j = 0; j < n; j++)
// if(arm[row[j]][j]!=0) {
// num--;
// break;
// }
return;
}
for (j = 1; j <= n; j++) {
for (k = 0; k < i; k++)
if(row[k]==j||Math.abs(k-i)==Math.abs(row[k]-j)/*||arm[j-1][row[k]]==0*/)
break;
if(k==i) {
row[k]=j;
queen(i+1, n);
}
}
}
public static void main(String[] args) {
int n,i,b,j;
Scanner scanner =new Scanner(System.in);
n=scanner.nextInt();
// for (int k = 0; k < n; k++) {
// for (int l = 0; l < n; l++) {
// arm[k][l]=scanner.nextInt();
// }
// }
queen(0, n);
System.out.println(num);
}
}