using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Please input a text with a *");

        string text =Console.ReadLine();

        Console.WriteLine("Hello World");

        newtext (text);

    }

    public static void newtext (string text){

        bool simulated=false;

        bool isunichek=true;

        bool firs=false;

        int h=0;

        bool isunicode=true;

        string textg="";

        int i=0;

        while (isunicode == true  && h< text.Length){

             isunicode =Char.IsLetterOrDigit(text,h );

            if( text.Substring(h,1).Equals("*") && firs ==false){

                isunicode = true;

                firs=true;

​

            }

            h++;

        }

        if ( text.Contains("*")&& isunicode == true){

            string texth =Console.ReadLine();

            Console.WriteLine(textg );

            while(i<= text.Length){

                    text=text.Replace("*", texth);

                    simulated=true;

                i++;

​

            }

            Console.WriteLine(textg );

            Console.WriteLine(text);

        }

        bool falsechking=false;

        for (int chkingtext=0; chkingtext<text.Length; chkingtext++){

             isunichek =Char.IsLetterOrDigit(text,chkingtext );

            if(isunichek == false){

                chkingtext=text.Length;

            }

            if( text.Substring(chkingtext).Equals("*")&&  isunichek == true  ){ 

            chkingtext=text.Length;

                falsechking=false;

            }

            else  {

                falsechking=true;

             }

            }

        if (simulated==false){

        if(falsechking==true && isunichek == true ) {

            Console.WriteLine("Error: no * in puted");

        }

        else if (isunichek == false ){

            Console.WriteLine("Invalid characters");

        }

        }

    }

}