using System; using System.Linq; using System.Collections.Generic;                  

public class Program

{   public static void Main()   

    {    var ValidationIdToInsert = new List<Int16>();  var ValidationIdToDelete = new List<Int16>(); var ValidationIdToUpdate = new List<Int16>();   var ValidationIdUpdateWith = new List<Int16>();

         var intersect = new List<Int16>();     

        List<Int16> Current = new List<Int16> { 61,15,10,12}; 

        List<Int16> New = new List<Int16> { 6,11,12,13,14,15};

         var NewNotInCurrent = New.Except(Current).ToList();        //new to insert

         var CurrentNotInNew = Current.Except(New).ToList();        //to delete

        intersect = New.Intersect(Current).ToList();        Console.WriteLine("intersect count: " + intersect.Count());         Console.WriteLine("NewNotInCurrent count: " + NewNotInCurrent.Count());     Console.WriteLine("CurrentNotInNew count: " + CurrentNotInNew.Count() +"\n");

        if(intersect != null && intersect.Count > 0)

        {

            if(NewNotInCurrent !=null && CurrentNotInNew!=null && (intersect.Count >= NewNotInCurrent.Count) && (intersect.Count >= CurrentNotInNew.Count))

            {

                 ValidationIdToInsert.AddRange(NewNotInCurrent.Except(intersect).ToList());                 

                //ValidationIdToInsert.AddRange(intersect.Except(NewNotInCurrent).ToList());

                ValidationIdToDelete.AddRange(CurrentNotInNew.Except(intersect).ToList());      

                Console.WriteLine("true 1");

            }

            else if(NewNotInCurrent !=null && CurrentNotInNew!=null && (intersect.Count < NewNotInCurrent.Count) && (intersect.Count < CurrentNotInNew.Count))

            {

                Console.WriteLine("true 2");

                //ValidationIdToInsert.AddRange(intersect.Except(NewNotInCurrent).ToList());

                ValidationIdToInsert.AddRange(NewNotInCurrent.Except(intersect).ToList());  

                ValidationIdToDelete.AddRange(CurrentNotInNew.Except(intersect).ToList());  

            }

            else if(NewNotInCurrent !=null && CurrentNotInNew!=null && (intersect.Count >= NewNotInCurrent.Count) && (intersect.Count < CurrentNotInNew.Count))

            {

                Console.WriteLine("true 3");

                //ValidationIdToInsert.AddRange(intersect.Except(NewNotInCurrent).ToList());

                ValidationIdToInsert.AddRange(NewNotInCurrent.Except(intersect).ToList());  

                ValidationIdToDelete.AddRange(CurrentNotInNew.Except(intersect).ToList());  

            }

            else if(NewNotInCurrent !=null && CurrentNotInNew!=null && (intersect.Count < NewNotInCurrent.Count) && (intersect.Count >= CurrentNotInNew.Count))

            {

                Console.WriteLine("true 4");

                //ValidationIdToInsert.AddRange(intersect.Except(NewNotInCurrent).ToList());

                ValidationIdToInsert.AddRange(NewNotInCurrent.Except(intersect).ToList());  

                ValidationIdToDelete.AddRange(CurrentNotInNew.Except(intersect).ToList());  

            }

        }       

         else

         {

             Console.WriteLine("true 3 : Intersect is empty");

            ValidationIdToInsert.AddRange(NewNotInCurrent);

             ValidationIdToDelete.AddRange(CurrentNotInNew);    

             //if()

         }

        string Insert = string.Empty; string Delete = string.Empty; string Update = string.Empty; string UpdateWith = string.Empty; string CommonInBoth = string.Empty; 

        string Newstr = string.Empty; string Currentstr = string.Empty;      

         foreach(var item in Current)

          {      

             Currentstr += item + ",";          

          }

         Console.WriteLine("Current List: " + Currentstr);

             foreach(var item in New)

          {      

             Newstr += item + ",";          

          }

         Console.WriteLine("New List: " + Newstr + "\n");

         foreach(var item in intersect)

          {      

             CommonInBoth += item + ",";            

          }

         Console.WriteLine("CommonInBoth List: " + CommonInBoth);

        foreach(var item in ValidationIdToInsert)

          {      

             Insert += item + ",";          

          }

         Console.WriteLine("Insert List: " + Insert);

        foreach(var item in ValidationIdToDelete)

          {      

             Delete += item + ",";          

          }

         Console.WriteLine("Delete List: " + Delete);

        foreach(var item in ValidationIdToUpdate)

          {      

             Update += item + ",";          

          }

         Console.WriteLine("Update List: " + Update);

        foreach(var item in ValidationIdUpdateWith)

          {      

             UpdateWith += item + ",";          

          }

         Console.WriteLine("UpdateWith List: " + UpdateWith);       

    }

}