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 if(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