#include <iostream>
using namespace std;
const int MAXN = 100000 + 5;

int n, m, cnt, ans[MAXN];

bool isPrime(int x)
{
    for (int i = 2; i * i <= x; ++i)
    {
        if (x % i == 0) return false;
    }
    return true;
}

bool isRealPrime(int x)
{
    int fan = 0;
    while (x)
    {
        fan = fan * 10 + x % 10;
        x /= 10;
    }
    if (isPrime(x) && isPrime(fan)) return true;
    return false;
}

int main()
{
    cin >> m >> n;
    for (int i = m; i <= n; ++i)
    {
        if (isRealPrime(i)) ans[++cnt] = i;
    }
    for (int i = 1; i <= cnt; ++i)
    {
        cout << ans[i];
        if (i != cnt) cout << ",";
    }
    if (!cnt) cout << "No";
    return 0;
}

My Output:
10,11,13,14,16,17,20,30,31,32,34,35