import java.util.Scanner;
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