#include<iostream>
using namespace std;
int Reverse(int n){
    int answer=0;
    while(n){
        answer*=10;
        answer+=n%10;
        n/=10;
    }
    return answer;
}
int main(){
    for(int n=1;n<256;n++){
        if(n*n==Reverse(n*n)){
            cout<<n<<endl;
        }
    }
}