using System;
using System.IO;
using System.Collections.Generic;
using System.Linq;

class Failivordlus
{
    public static void Main(string[] arg)
    {
        File.WriteAllLines("ainultujujad.txt",
          File.ReadAllLines("ujujad.txt").Except(File.ReadAllLines("jooksjad.txt"))
        );
    }
}
/*
>type ujujad.txt
Kati
Siiri
Madis
Mart

>type jooksjad.txt
Juku
Kati
Mati

>type ainultujujad.txt
Siiri
Madis
Mart
 
>c:\WINDOWS\Microsoft.NET\Framework\v4.0.30319\csc.exe Failivordlus.cs
*/