import java.util.*;
public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();

        if(n>=100 && n<112){
            System.out.println(111);
        }else if(n>=112 && n<=222){
            System.out.println(222);
        }else if(n>222 && n<=333){
            System.out.println(333);
        }else if(n>333 && n<=444){
            System.out.println(444);
        }else if(n>444 && n<=555){
            System.out.println(555);
        }else if(n>555 && n<=666){
            System.out.println(666);
        }else if(n>666 && n<=777){
            System.out.println(777);
        }else if(n>777 && n<=888){
            System.out.println(888);
        }else if(n>888 && n<=999){
            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