#include <cstdio>
#include <cmath>
#include <string>
using namespace std;
bool isPrime(int n) {
if (n <= 1)
return false;
for (int i = 2; i <= sqrt(n); i++) {
if (!(n % i))
return false;
}
return true;
}
bool isPalindrome(int d) {
string s = to_string(d);
int left = 0, right = s.size() - 1;
while (left < right) if (s[left++] != s[right--]) return false;
return true;
}
int main() {
int a, b;
scanf("%d %d", &a, &b);
for (; a <= b; a++) if (isPalindrome(a) && isPrime(a)) printf("%d\n", a);
return 0;
}
先判断是否回文再判断素数还是TLE
awa