import java.util.*;

class Main{

	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);

		int N = sc.nextInt();

		int ans = 0;

		for(int i = 1; i<10; i++){
			int a = 111;
			if((a*i) >= N){
				ans = a*i;
				break;
			}
		}

		System.out.println(ans);


	}
}
/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