I

#include <iostream>
#include <cmath>

using namespace std;

bool isPrime(const int &n)
{
    if (n == 1)
        return false;
    if ((n == 2) || (n == 3))
        return true;
    int sqr = sqrt((double)n);
    for (int i = 2; i<=sqr+2; i++)
        if ((n%i) == 0)
            return false;
    return true;
}

int main()
{
    int k, n, j = 0;
    bool flag = false;
    cin >> k >> n;
    int size = ((double)(2*n))/log((double)(2*n)) + 2000;

    int *arr = new int[size];

    for (int i = 0; i<=2*n; i++)
    {
        if (isPrime(i))
        {
            arr[j] = i;
            j++;
        }
    }

    for (int i = 1; i<=j; i++)
    {
        if ((arr[i] == ((arr[i-1]+arr[i+1])/2.0))&&(arr[i]<=n)&&(arr[i]>=k))
        {
            cout << arr[i] << " ";
            flag = true;
        }
    }

    if (!flag)
        cout << "0" << endl;

    return 0;
}