#include <stdio.h>
#include <stdbool.h>

// A function that checks whether a number is prime or not
int isPrime(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() {
    // Find prime numbers starting with 5 and having 3 digits
    for (int sayi = 500; sayi <= 599; sayi++) {
        if (sayi % 10 == 3 || sayi % 10 == 7) {
            if (isPrime(sayi)) {
                printf("%d\n", sayi);
            }
        }
    }

    return 0;
}