how to get a SUM in Linq?

c#, linq

Solution

Group the items by `Id` and then sum the `Count`s in each group:

var result = items.GroupBy(x => x.Id)
                  .Select(g => new { Id = g.Key, Sum = g.Sum(x => x.Count) });

Problem

I need to do the following, I have a `List` with a class which contains 2 integer id and count Now I want to do the following linq query: ``` get the sum of the count for each id ``` but there can be items with the same id, so it should be summerized e.g.: ``` id=1, count=12 id=2, count=1 id=1, count=2 ``` sould be: ``` id=1 -> sum 14 id=2 -> sum 1 ``` how to do this?

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