using System;

using System.Linq;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        Dictionary<string, string> prev=new Dictionary<string, string>();

        Dictionary<string, string> next=new Dictionary<string, string>();

        prev.Add("Key1","Value1");

        prev.Add("Key2","Value2");

        prev.Add("Key3","Value3");

        prev.Add("Key4","Value4");

        prev.Add("Key5","Value5");

        next.Add("Key1","Value1");

        next.Add("Key2","Value2");

        next.Add("Key3","Value3");

        next.Add("Key4","Value4");

        next.Add("Key5","Value6");

        var exc=prev.Except(next).ToList();

        foreach(var kvp in exc)

        {

            Console.WriteLine($"{kvp.Key}, {kvp.Value}");

        }

    }

}