/* package whatever; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
       int n;
        n=3;
        mystery (n);
 	}
	

    public static void mystery(int n)
    {
    	int k;
    	for (k=0;k<n;k++)
    	{

        	mystery (k);
        	System.out.print(k);
    	}
    }
	
}