public class Solution {

public static void main(String[] args) {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
    Scanner scan = new Scanner(System.in);
    int n = scan.nextInt();
    MyCalculator mycalculator = new MyCalculator();
    System.out.println("I implemented: AdvancedArithmetic");
    System.out.print(mycalculator.divisor_sum(n));
}

}

interface AdvancedArithmetic { int divisor_sum(int n); }

class MyCalculator implements AdvancedArithmetic{ int suma =0; public int divisor_sum(int n){ for(int i=1; i<=n; i++){ if(n%i==0){ suma+=i; } } return suma; } }

Java Code :

class MyCalculator implements AdvancedArithmetic {

public int divisor_sum(int n){
     List<Integer> ls = new ArrayList<>();
    for(int i=1;i<1001;i++){
        if(n % i == 0){
            ls.add(i);
        }
    }
    int sum=0;
    for(int j : ls)
    {
        sum+=j;
    }
    return sum;
}

}

class MyCalculator implements AdvancedArithmetic{ public int divisor_sum(int n){ int sum=0; for(int i=1;i<=n;i++){ if(n%i==0){ sum=sum+i; } } return sum; } }

simple code bro

import java.io.; import java.util.;

public class Solution {

public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int n = sc.nextInt();
    MyCalculator calc = new MyCalculator();
    System.out.println("I implemented: AdvancedArithmetic");
    System.out.println(calc.divisor_sum(n));
  }

} interface AdvancedArithmetic{
public int divisor_sum(int n); }
class MyCalculator implements AdvancedArithmetic{ @Override public int divisor_sum(int n ){ int sum=0 ; if(n>=1 && n<=1000){ for(int i = 1 ; i <=n ; i++){ if(n%i ==0){ sum+=i; }}} return sum; }

}

import java.io.; import java.util.;

interface divSum { int divisor_sum(int n); }

class AdvancedArithmetic implements divSum { public int divisor_sum(int n){ int sum = 0; for(int i=1; i<=n; i++) { if(n%i==0) sum = sum + i; } return(sum); } }

public class Solution {

public static void main(String[] args) {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
    Scanner sc = new Scanner(System.in);
    int n = sc.nextInt();
    AdvancedArithmetic a = new AdvancedArithmetic();
    int ans = a.divisor_sum(n);
    System.out.println("I implemented: "+a.getClass().getName());
    System.out.print(ans);
}

}