import java.util.*;
public class Main {
    public static void main(String args[]) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        while (true) {
            if (ok(n)) {
                System.out.println(n);
                return;
            }
            n++;
        }
    }
    public static boolean ok(int x) {
        boolean ret = true;
        int r = x % 10;
        while (x / 10 > 0) {
            x /= 10;
            if (x % 10 != r) ret = false;
            else r = x % 10;
        }
        return ret;
    }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz