import java.io.*;

public class factorial {

public static void main(String ars[])
{
double f=1;
try{

BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

System.out.println("Ingresa un numero:");
String n1 = br.readLine();

int s = Integer.parseInt(n1);
for (int i=1; i<=s; i++)

f=f*i;

System.out.println("Factorial de "+ s +" es: " + f);

}
catch(Exception e){

System.out.println("Error en los datos");

}

}

}