using System.CodeDom.Compiler;

using System.Collections.Generic;

using System.Collections;

using System.ComponentModel;

using System.Diagnostics.CodeAnalysis;

using System.Globalization;

using System.IO;

using System.Linq;

using System.Reflection;

using System.Runtime.Serialization;

using System.Text.RegularExpressions;

using System.Text;

using System;

​

public class Program

{   

​

    public static int howManyGames(int p, int d, int m, int s)

    {

        var res = 0;

        var currPrice = p;

        //If we cannot buy the first game - return 0

        if(p > s)

            return res;

        //Determines how many games we will get from this buying logic

        while(s >= m)

        {

            //Buys the first game

            if(res == 0)

            {

                res++;

                s -= p;

            }

            //Else, buys every n + 1 game

            else

            {

                //Determines the max price before hitting m

                currPrice = Math.Max(currPrice - d, m);

                res++;

                s -= currPrice;

            }

        }

        return res;

​

    }

    public static void Main()

    {

        var p = 20;

        var d = 3;

        var m = 6;

        var s = 60;

        var res = howManyGames(p, d, m, s);

        Console.WriteLine("Res: " + res);

    }

}