4346: GESP C++四级样题_3绝对素数

#include <iostream>
using namespace std;
bool is_prime(int num) {
    if (num < 2)
        return false;
    for (int i = 2; i * i <= num; i++) {
        if (num % i == 0)
            return false;
    }
    return true;
}
int main() {
    int a = 0, b = 0;
    cin >> a >> b;
    for (int num = a; num <= b; num++) {
        if (is_prime(num)) {
            int reversed_num = (num % 10) * 10 + num / 10;
            if (is_prime(reversed_num))
                cout << num << endl;
        }
    }
    return 0;
}