import java.util.*;

public class Main{
      public static void main(String[] args) {
            Scanner sc = new Scanner(System.in);
            int N = sc.nextInt();
            if(N <= 111){
              System.out.println(111);
            } else if(N <= 222){
              System.out.println(222);
            } else if(N <= 333){
              System.out.println(333);
            } else if(N <= 444){
              System.out.println(444);
            } else if(N <= 555){
              System.out.println(555);
            } else if(N <= 666){
              System.out.println(666);
            } else if(N <= 777){
              System.out.println(777);
            } else if(N <= 888){
              System.out.println(888);
            } else {
              System.out.println(999);
            }
          }
}
/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