using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    public static void Main()

    {

        //////////////////Courses///////////////

        Application app1 = new Application()

        {

            Name =  "Adobe Acrobat",

            Id = 1

        };

        Application app2 = new Application()

        {

            Name = "Audacity",

            Id = 2

        };

        Application app3 = new Application()

        {

            Name =  "Visual Studio 15",

            Id = 3

        };

        List<Application> application  = new List<Application>();

        application.Add(app1);

        application.Add(app2);

        application.Add(app3);

        var app_Id2 = application.Where(ap => ap.Id ==2 ).ToList();

        //////////////////Students///////////////

        List<Device> dev = new List<Device>();

        dev.Add( new Device()

                      {

                          Name = "Device1", 

                          Applications = app_Id2 // app ID =2

                      });   

         dev.Add( new Device()

                      {

                         Name = "Device2", 

                         Applications = application // app IDs = 1,2,3,

                      });   

         dev.Add( new Device()

                      {

                          Name = "Device3", 

                          Applications = new List<Application> {app1, app2}

                      });

         dev.Add( new Device()

                      {

                          Name = "Device4", 

                          Applications = new List<Application>()

                      });   

        var devices = dev.

            SelectMany( a => a.Applications, (d, a) => new {d, a}).

            Where(a => a.a.Name.Contains("Adobe"));

        var appls = application.            

            SelectMany( d => d.Devices, (d, a) => new {d, a});

      //////////////////Show data///////////////            

    foreach (var item in devices )

        {

            //Console.WriteLine("{0}, {1}", item.d.Name, item.a.Name);  

        }

​

​

 foreach (var dv in dev)  

    foreach (var app in dv.Applications)        

     Console.WriteLine("{0}, {1}, {2}",dv.Name, app.Name, app.Id); 

}

}

​

////////////////////Model defn.///////////////////////////

​

public class Device 

{

    public int Id {get; set;}

    public string Name {get; set;}  

    public virtual ICollection<Application> Applications { get; set; }

}

​

public class Application 

{

    public int Id {get; set;}

    public string Name {get; set;}  

    public virtual ICollection<Device> Devices { get; set; }

}