import java.util.Scanner;

public class Main{
    public static void main(String[] args){
	Scanner sc = new Scanner(System.in);
	int N = sc.nextInt();
	int re=0;
	if(N<=111) re=111;
	else if(N<=222) re=222;
	else if(N<=333) re=333;
	else if(N<=444) re=444;
	else if(N<=555) re=555;
	else if(N<=666) re=666;
	else if(N<=777) re=777;
	else if(N<=888) re=888;
	else re=999;
	System.out.print(re);
    }
}

/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