import java.util.*;
public class Problem23 {

   // Compute sum of proper divisors
   public static int sumDivisors(int num) {
      int sum = 1; //1 is a proper divisor
      for(int i=2;i*i<num;i++) {
         if(num % i == 0) {
            sum += i;
            sum += num / i;
         }
      }
      return sum;
   }

   public static int[] getAbundant(int limit) {
      int[] result = new int[50];
      int index = 0;
      for(int i=12;i<limit;i++) {
         if(sumDivisors(i) > i) {
            if(index == result.length) {
               int[] tmp = new int[index*2];
               for(int j=0;j<index;j++) {
                  tmp[j] = result[j];
               }
               result = tmp;
               result[index] = i;
               index++;
            } else {
               result[index] = i;
               index++;
            }
         }
      }
      int[] tmp = new int[index];
      for(int i=0;i<index;i++) {
         tmp[i] = result[i];
      }
      return tmp;
   }

   public static void main(String[] args) {
      int sum = 0;
      int[] abundant = getAbundant(28124); //Get all abundant numbers
      for(int i=0;i<28124;i++) {
         boolean done = false;
         for(int j=0;j<abundant.length && abundant[j] < i && !done;j++) { //First part of pair
            int p = abundant[j];
            for(int k=j;k<abundant.length && abundant[k] < i && !done;k++) { //Second part of pair
               if(p + abundant[k] == i) {
                  System.out.println(i + " is the sum of "+p+" and "+abundant[k]);
                  done = true;
               }
            }
         }
         if(!done) { //If no pair was found
            System.out.println(i + "cannot be written as a sum of abundant numbers");
            sum += i;
         }
      }
      System.out.println(sum);
   }
}