public class exerc3 
{
        int fatorial = 13; 
        public exerc3()
        {   
                int z = Metodo_Calc_Fatorial(fatorial);
                System.out.println("" + z);  
        }
        public int Metodo_Calc_Fatorial (int num)
        {
              int res = 1;
              while(num >1)
              {
                    res = res * num; 
                    num = num -1; 
              } 
              return res;   
        }        
        public static void main (String args [])
        {new exerc3();}
}