Multiple values for single key

Question

I have a list that contains Categories and their accept/reject counts but there is a problem with this list. I'm using a LINQ query to access the data, and I grouped them by both category name and Accept/Reject Code(ResultCode). So the data is in this form:

Almost all of the Categories have both AP counts and RJ counts. And what I'm trying to do is to show each Category's accept and reject count. What should I use? Hashtables don't fit in this problem, I tried Dictionary with int List as value but couldn't add when the same key appeared.

UPDATE:

List<ModReportingDM.ReportObjects.AllCategories> allcats = new List<ModReportingDM.ReportObjects.AllCategories>();
Dictionary<string, ModReportingDM.ReportObjects.ResultCode> dict = new Dictionary<string, ModReportingDM.ReportObjects.ResultCode>();
ModReportingDM.ReportObjects.ResultCode x = new ModReportingDM.ReportObjects.ResultCode();
allcats = reportBLL.GetAllCats(model.ModId, model.ReportStartDate, model.ReportEndDate);
        if (allcats != null)
        {
            model.AllCatsList = new List<ModReportingDM.ReportObjects.AllCategories>();

            foreach (var item in allcats)
            {
                x.Accepted = item.Count;
                x.Rejected = item.Count;
                dict.Add(item.Category, x);

            }
        }

Query:

public List<AllCategories> GetAllCats(int modId, DateTime startDate, DateTime endDate)
    {
        using (entities = new ModReportingEntities())
        {
            var query = (from c in entities.Content
                         where c.ModId == modId && c.CreatedTime >= startDate && c.CreatedTime <= endDate && c.Category != null
                         group c by new { c.Category, c.ResultCode } into g
                         orderby g.Count() ascending
                         select new AllCategories
                         {
                             Category = g.Key.Category,
                             ResultCode = g.Key.ResultCode,
                             AcceptCount = g.Count(),
                             RejectCount = g.Count()
                         });

            return query.ToList();
        }
    }

Answer 1

What i would do is create a ResultCode class:

public class ResultCode
{
    public int Ap { get; set; }
    public int Rj { get; set; }
}

and then use a Dictionary<string, ResultCode> which maps each category to its report.

You could also take a different approach using a Tuple<T1, T2> (which personally i like less) which simply maps your key to two distinct values:

Dictionary<string, Tuple<int, int>> categoryToResultCode;