#include<iostream>
using namespace std;
int main() {
    unsigned long long n,a,ans = 0;
    for (long long i = 2;i <= 10000;i++) {
        a = i * i;
        if (i * i % 10 == i || i * i % 100 == i || i * i % 1000 == i) {
            cout << i << endl;
            ans += 1;
    	}
    }
    cout << ans << endl;
	return 0;
}