Code First EF 4.1 : Building Many to Many Relationship

public class Emp
{
    public Emp()
    {
        Projects = new HashSet<Project>();
    }

    public int EmpId { get; set; }
    public string EmpName { get; set; }
    public ICollection<Project> Projects { get; set; }
}

public class Project
{
    public Project()
    {
        Emps = new HashSet<Emp>();
    }

    public int ProjectId { get; set; }
    public string ProjectName { get; set; }
    public ICollection<Emp> Emps { get; set; }
}

public class EmpContext : DbContext
{
    public DbSet<Emp> Emps { get; set; }
    public DbSet<Project> Projects { get; set; }
}

class Program
{
    static void Main(string[] args)
    {
        var p1 = new Project() { ProjectName = "Fun Boat" };
        var p2 = new Project() { ProjectName = "Jumbo Jet" };
        var p3 = new Project() { ProjectName = "Free Zoo" };

        var e1 = new Emp() { EmpName = "Wriju" };
        var e2 = new Emp() { EmpName = "Wrishika" };
        var e3 = new Emp() { EmpName = "Saswati" };

        p1.Emps.Add(e1);
        p1.Emps.Add(e2);

        p2.Emps.Add(e2);
        p2.Emps.Add(e3);

        p3.Emps.Add(e3);
        p3.Emps.Add(e1);

        using (var ctx = new EmpContext())
        {
            ctx.Projects.Add(p1);
            ctx.Projects.Add(p2);
            ctx.Projects.Add(p3);
                
            ctx.SaveChanges();
        }
    }
}