package Lan;
import java.util.;
public class Main {
/
*/
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
int num = in.nextInt();
int max = 99999999;
for(int i = num+1;i<=max;i++) {
String s=nextHuiWen(i);
if(s != null) {
System.out.println(s);
break;
}
}
for(int i = num+1;i<=max;i++) {
String s = nextXing(i);
if(s != null) {
System.out.println(s);
break;
}
}
}
static String nextHuiWen(int i) {
String str = i+"";
//长度为8 必然为偶长度
for(int j = 0;j<str.length()/2;j++) {
if(str.charAt(str.length()-1-j) != str.charAt(j)) {
return null;
}
}
return str;
}
static String nextXing(int i) {
String str = i+"";
char A = str.charAt(0);
char B = str.charAt(1);
if(A == str.charAt(2) && B == str.charAt(3)
&& B == str.charAt(4) && A == str.charAt(5)
&& B == str.charAt(6) && A == str.charAt(7)) {
return str;
}
return null;
}
}