using System;

using System.Linq;

using System.Collections.Generic;

​

public class Program

{

    public static void Main()

    {

        var list = new List<int>{1, 2, 3, 4, 5};

        var pairs = list.Take(list.Count() - 1).Select((z, index) => new

        {

        a = z, b = list[index + 1]

        }).ToList();

        pairs.ForEach(p => Console.Write("(" + p.a + "," + p.b + ") "));

    }

}