import java.util.Scanner;
public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		
		int n = sc.nextInt();
		
		int intAns = 0;
		
		for (int i = 1; i < 10; i++) {
			
			n -= 111;
			
			if (n <= 0) {
				intAns = i;
				break;
			}
		}
		
		String ans = String.valueOf(intAns);
		
		System.out.println(ans + ans + 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