using System;

using System.Collections.Generic;

public class Program

{

    /* 

     * Example: 100; Base = 7

     * 100 / 7 = 14; 100 % 7 = 2

     * 14 / 7 = 2; 14 % 7 = 0

     * 2 / 7 = 0; 2 % 7 = 2

     * Output: 202

    */  

    public static string ConvertToBase7(int num) 

    {

        if (num == 0)

            return "0";

        int sign = num >= 0 ? 1 : -1;

        num *= sign;

        var res = new List<int>();

        while (num > 0)

        {

            res.Add(num % 7);

            num /= 7;

        }

        res.Reverse();

        string str = string.Join("", res);

        return sign == -1 ? "-" + str : str;

    }

    public static void Main()

    {

        Console.WriteLine("UniLecs");

        // tests

        Console.WriteLine(ConvertToBase7(6).ToString()); // 6

        Console.WriteLine(ConvertToBase7(7).ToString()); // 10

        Console.WriteLine(ConvertToBase7(8).ToString()); // 11

        Console.WriteLine(ConvertToBase7(100).ToString()); // 202

    }

}