#include <iostream> #include <vector> #include <algorithm> bool isPrime(int n) { if (n <= 1) return false; if (n == 2) return true; if (n % 2 == 0) return false; for (int i = 3; i * i <= n; i += 2) { if (n % i == 0) return false; } return true; } int reverse(int n) { int reversed = 0; while (n != 0) { reversed = reversed * 10 + n % 10; n /= 10; } return reversed; } int main() { int M, N; std::cin >> M >> N; std::vector<int> absolutePrimes; for (int i = M; i <= N; i++) { if (isPrime(i) && isPrime(reverse(i))) { absolutePrimes.push_back(i); } } if (absolutePrimes.empty()) { std::cout << "No" << std::endl; } else { for (size_t i = 0; i < absolutePrimes.size(); i++) { if (i != 0) std::cout << ","; std::cout << absolutePrimes[i]; } std::cout << std::endl; } return 0; }