using System;

using System.Linq;

​

public class Program

{

    public static void Main()

    {

        var fruits = new[] { "Apple", "Apple", "Banana", "Banana" };

        var quantities = fruits.GroupBy(

           (f) => f,

           (f) => f,  

           (f, fs) => new Quantity<string>(f, fs.Count())

        );

        // Print the result

        foreach (var quant in quantities)

        {

            Console.WriteLine(quant.Item + " (" + quant.Count + ")");   

        }

    }

}

​

public class Quantity<T>

{

    public Quantity(T item, int count)

    {

        Item = item;

        Count = count;

    }

​

    public T Item { get; private set; }

    public int Count { get; private set; }

}