How get count of each distinct item in generic List in C#

Question

I have for example this list.

List<int> numbers = new List<int>() { 1, 1, 2, 2, 3, 3, 4 };

And I want to get another list with count of each distinct item in that list, so something like this 2,2,2,1. I guess it is possible to reach it by using foreach, but is it possible in easier way(LINQ maybe)? Thanks.

Do a grouping by elements of the list – Vsevolod Goloviznin Jan 25 '15 at 16:07 — Vsevolod Goloviznin, Jan 25 '15 at 16:07

score 8 · Answer 1 · answered Jan 25 '15 at 16:08

var counts = numbers.GroupBy(x => x)
                    .Select(g => new { Number = g.Key, Count = g.Count() })
                    .ToList();

Instead of anonymous objects, you can use a dictionary too

var counts = numbers.GroupBy(x => x)
                    .ToDictionary(x => x.Key, x => x.Count());

How get count of each distinct item in generic List in C#

1 Answers1