using System;

public class Program

{

    private static float _expToLevelBase = 100f;

    private static float _expToLevelMult = 1.25f;

    public static void Main()

    {

        for (int ii = 0; ii < 100; ii++)

        {

            int result1 = GetExpReq(ii);

            int result2 = GetExpReqClosed(ii);

            string result = (result1 == result2) ? "OK!" : "NO.";

            Console.WriteLine(ii + ": " + result + " Loop Method: " + result1 + " Closed Method: " + result2);

        }

    }

    public static int GetExpReq(int level)

    {

        float total = _expToLevelBase;

        float lastHorribleNumber = _expToLevelBase;

        for (int i = 0; i < level; i++)

        {

            lastHorribleNumber = lastHorribleNumber * _expToLevelMult;

            total += lastHorribleNumber;

        }

        return (int)total;

    }

    public static int GetExpReqClosed(int level)

    {

       return (int)(_expToLevelBase*(1-Math.Pow(_expToLevelMult,level + 1))/(1-_expToLevelMult));

    }

}