AdventOfCode23/Day4/ScratchCard.cs

namespace Day4;

public class ScratchCard
{
    public int Id { get; }
    public ISet<int> Winning { get; } = new HashSet<int>();
    public ISet<int> Draw { get; } = new HashSet<int>();

    public ScratchCard(int id)
    {
        Id = id;
    }
    
    public int GetMatches()
    {
        return Draw.Select(draw => Winning.Contains(draw) ? 1 : 0).Sum();
    }

    public int GetScore()
    {
        var matches = GetMatches();
        return matches > 0 ? (int)Math.Pow(2, matches - 1) : 0;
    }
}