import java.util.*;
class Main
{
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n=sc.nextInt();
		StringBuffer sb = new StringBuffer();
		for(int i=n;i<=999;i++)
		{
			if(check(i))
			{
				System.out.println(i);
				break;
			}

		}
	}

	static boolean check(int n)
	{
		int x=n%10;
		n/=10;
		if(n%10!=x)
			return false;
		n/=10;
		if(n%10!=x)
			return false;
		return true;
	}
}
/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