Emirps

import java.util.Scanner;
import java.util.SortedSet;
import java.util.TreeSet;

/**
 * Tuenti Programming Contest
 * Challenge 3: Emirps
 * @author alefhidalgo [at] gmail [dot] com
 */
public class Emirps {

    /* Pre-computated Emirps */
    private SortedSet<Long> preComputedEmirps;
    /* Last pre-computated up to */
    private long lastComputedUpTo = 0;
    /**
     * Constructor
     */
    public Emirps() {
        preComputedEmirps = new TreeSet<Long>();
    }
    /**
     * Pre-computated Emirps numbers for a best performance
     * @param from
     * @param to
     */
    private void preComp(long from, long to) {
        for (long i = from; i < to; i++) {
            if (isEmirp(i)) {
                preComputedEmirps.add(i);
            }
        }
        lastComputedUpTo = to;
    }
    /**
     * IsPrime
     * @param n
     * @return
     */
    private boolean isPrime(Long n) {
        if (n < 2)
            return false;
        if (n == 2 || n == 3)
            return true;
        if (n % 2 == 0 || n % 3 == 0)
            return false;
        long sqrtN = (long) Math.sqrt(n) + 1;
        for (long i = 6L; i <= sqrtN; i += 6) {
            if (n % (i - 1) == 0 || n % (i + 1) == 0)
                return false;
        }
        return true;
    }
    /**
     * IsEmirp
     * @param n
     * @return
     */
    private boolean isEmirp(Long n) {
        Long reverse = new Long(new StringBuffer(n.toString()).reverse().toString());
        return isPrime(n) && isPrime(reverse) && n.compareTo(reverse)!=0;
    }

    /**
     * Calculate emirps sum
     * @param number
     * @return
     */
    public Long calculate(Long number) {
        long result = 0;
        if (number > lastComputedUpTo) {
            preComp(lastComputedUpTo, number);
        }
        for (Long i : preComputedEmirps) {
            if (i < number) {
                result += i;
            }else {
                break;
            }
        }
        return result;
    }

    public static void main(String args[]) {
        Emirps emirps = new Emirps();
        Scanner in = new Scanner(System.in);
         while (in.hasNextLine()) {
             System.out.println(emirps.calculate(in.nextLong()));
         }

    }
}