334 Reporter

PointCalculator.cs

public class PointCalculator
{
        private int _power, _penalty;

        public PointCalculator(int power = 1, int penalty = 2)
        {
            _power = power;
            _penalty = penalty == default ? 1 : penalty;
        }

        public int Calculate(TimeSpan delay)
        {
            var duration = delay.Duration().TotalMilliseconds;
            return (int)Math.Floor(_power * (
                duration <    10 ? 1000 - duration *  10 :
                duration <   100 ?  940 - duration *   4 :
                duration <  1000 ?  565 - duration /   4 :
                duration < 10000 ?  325 - duration / 100 :
                duration < 60000 ?  245 - duration / 500 : 0) / (
                delay == delay.Duration() ? 1 : _penalty));
        }
}

Rank.cs

public int Rank => RankBorder.Select((b, i) => (b, i)).FirstOrDefault(x => x.b > Exp).i - 1;

public static IList<int> RankBorder => Enumerable.Range(0, 1000).Select(x => (x + 15) * x * 40).ToList();