#include <iostream>
using namespace std;

int reverse(int x){
    int revx = 0;
    while(x != 0){
        revx *= 10;
        revx += x % 10;
        x /= 10;
    }
    return revx;
}

int main() {
    for(int i = 0;i <= 256;i++){
        if(i*i == reverse(i*i)){
            cout<<i<<endl;
        }
    }
    return 0;
}
// 64 位输出请用 printf("%lld")