import java.util.*;

public class Main {
	public static void main(String[] args) {
      Scanner sc =new Scanner(System.in);
      int N = sc.nextInt();
      int ans =0;
      for (int i=N; i<=999; i++) {
        int i3 = i % 10;
        int i2 = (i % 100 - i3) /10;
        int i1 = (i - i2 * 10 - i3) / 100;
        if (i3 == i2 && i2 == i1) {
          ans = 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