content: import java.util.*;
  interface AdvancedArithmetic{
    int divisor_sum(int n);
  }
  
  //Write your code here
  class MyCalculator implements AdvancedArithmetic{
      public int divisor_sum(int n)
      {
          int sum = n;
          for(int i=1; i<= n/2; i++)
          {
              if(n % i == 0)
                  sum += i;
          }
          return sum;
      }
  }
  class Solution{
      public static void main(String []args){
          MyCalculator my_calculator = new MyCalculator();
          System.out.print("I implemented: ");
          ImplementedInterfaceNames(my_calculator);
          Scanner sc = new Scanner(System.in);
          int n = sc.nextInt();
          System.out.print(my_calculator.divisor_sum(n) + "\n");
        	sc.close();
      }
      /*
       *  ImplementedInterfaceNames method takes an object and prints the name of the interfaces it implemented
       */
      static void ImplementedInterfaceNames(Object o){
          Class[] theInterfaces = o.getClass().getInterfaces();
          for (int i = 0; i < theInterfaces.length; i++){
              String interfaceName = theInterfaces[i].getName();
              System.out.println(interfaceName);
          }
      }
  }
  
  