practice/FiveLetters/Model/FiveLettersItemResult.cs

using System.Collections.Generic;

namespace FiveLetters.Model
{
    public class FiveLettersItemResult
    {
        public List<FiveLettersItemLetterResult> Results { get; set; }

        public FiveLettersItemResult(List<FiveLettersItemLetterResult> results)
        {
            Results = results;
        }

        public HashSet<char> GetLettersFullMatch()
        {
            var hs = new HashSet<char>();
            foreach(var res in Results)
            {
                if (res.Result == EResultLetterType.FullMatch)
                {
                    hs.Add(res.Letter);
                }
            }
            return hs;
        }
        public HashSet<char> GetLettersPartialMatch()
        {
            var hs = new HashSet<char>();
            foreach (var res in Results)
            {
                if (res.Result == EResultLetterType.PartialMatch)
                {
                    hs.Add(res.Letter);
                }
            }
            return hs;
        }
    }
}