AdventOfCode/AdventOfCode.Core/SolutionManager.cs

using AdventOfCode.Core.Shared;

namespace AdventOfCode.Solutions
{
    public class SolutionManager
    {
        private readonly IChallange[] _challanges;

        public SolutionManager(IEnumerable<IChallange> challanges)
        {
            _challanges = challanges.ToArray();
        }

        public IEnumerable<IChallange> GetChallanges(Func<IChallange, bool> predicate)
        {
            return _challanges.Where(predicate);
        }

        public IChallange? GetChallange(int year, int day)
        {
            return _challanges.SingleOrDefault(challange => challange.Year == year && challange.Day == day);
        }
    }
}