static void Solution5() {
            int stones = 12500000;
            int year = 0;
            while (stones > 0) {
                stones -= ToRoman(year) * 250;
                stones = (year%43 == 0) ? (int) (stones*0.85) : stones;
                year++;
            }
            Console.WriteLine(--year + " - "+ -stones);
        }
        static int ToRoman(int number) {
            if (number >= 1000) return ToRoman(number - 1000)+1;
            if (number >= 900) return ToRoman(number - 900)+2;
            if (number >= 500) return  ToRoman(number - 500)+1;
            if (number >= 400) return  ToRoman(number - 400)+2;
            if (number >= 100) return ToRoman(number - 100)+1;
            if (number >= 90) return  ToRoman(number - 90)+2;
            if (number >= 50) return ToRoman(number - 50)+1;
            if (number >= 40) return ToRoman(number - 40)+2;
            if (number >= 10) return ToRoman(number - 10)+1;
            if (number >= 9) return  ToRoman(number - 9)+2;
            if (number >= 5) return  ToRoman(number - 5)+1;
            if (number >= 4) return ToRoman(number - 4)+2;
            if (number >= 1) return ToRoman(number - 1)+1;
            return 0;
        }