using System;

using System.Linq;

using System.Collections.Generic;

​

public class Program

{

    public static void Main()

    {

        List<string> items = new List<string>();

        items.Add("green");

        items.Add("black");

        items.Add("blue");

        items.Add("blue");

        var results = items.Select(p => p).Distinct().Count() < items.Count;

        var repeat = items.GroupBy(x=>x)

            .Where(g=>g.Count() > 1)

            .Select(y=> new { Element = y.Key, Counter = y.Count() })

            .ToList();

        Console.WriteLine(results);

        repeat.ForEach(r=> Console.WriteLine(r.Element + " " + r.Counter));

    }

}