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How to explicitly specify types when grouping in LINQ?

I play with GroupBy (...) and I understand that although I work, I prefer not to use var. Call me anal, but I like to know what type I have when I have. (Of course, I'm not an ideologist, and when the syntax makes me lose my eyes, I use var. Nevertheless, it's nice to know how to draw it if they want to appear.)

var grouping = array.GroupBy(element => element.DayOfWeek);
foreach (var group in grouping)
{
  Console.WriteLine("Group " + group.Key);
  foreach (var value in group)
    Console.WriteLine(value.Start);
}

According to intellisense, I am generating something like IGrouping, but when I tried to enter it explicitly, something strange happened. I came to the next.

IEnumerable<IGrouping<DayOfWeek, TimeInfo>> grouping 
  = array.GroupBy(element => element.DayOfWeek);
foreach (IGrouping<DayOfWeek, TimeInfo> group in grouping)
{
  Console.WriteLine("Group " + group.Key);
  foreach (TimeInfo value in group)
    Console.WriteLine(value.Start);
}

My question is twofold. Is the correct and narrowest area below the result? If not, how can I fix it additionally?

, , . ( ). , 1D- 2D . - SelectMany, . ( - google.)

+4
2

?

, IGrouping<TKey,TElement> IEnumerable<TElement>, :

IEnumerable<IEnumerable<TimeInfo>> grouping =
  = array.GroupBy(element => element.DayOfWeek);

, ( ) ; .

ToArray():

TimeInfo[][] groups = 
   grouping.Select(g => g.ToArray()).ToArray();
+4

, , . , foreach class IGrouping , . , , IGrouping, , , , groupby, , : IGrouping

ToDictionary , , , .

, Select with ToArray, ToList .

+1

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