import java.math.BigInteger;
import java.util.HashMap;
import java.util.Map;
public class Main {
public static void main(String[] args) {
System.out.println(fac(0));
System.out.println(fac(1));
System.out.println(fac(2));
System.out.println(fac(3));
System.out.println(fac(5));
System.out.println(fac(22));
}
public static String fac(int n) {
Map<Integer, BigInteger> map = new HashMap<>();
BigInteger atual = BigInteger.ONE;
for (int i = 1; i <= n; i++) {
atual = atual.multiply(BigInteger.valueOf(i));
map.put(i, atual);
}
return atual.toString();
}
}