import java.util.*;
public class Two2018 {
public static void main(String[] args) {
Scanner in=new Scanner(System.in);
int []shuzu=new int [100];
int flag=1;
int i,j;
for(i=0;shuzu[i]!=-1;i++){
shuzu[i]=in.nextInt();
String ss=Integer.toString(shuzu[i]);
int len=ss.length();
for(j=0;j<len/2;j++){
if(ss.charAt(j)!=ss.charAt(len-j-1))
{
flag=0;
break;
}
}
if(flag==1){
System.out.print(shuzu[i]+" ");
}else{
flag=1;
}
}
}
}