using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    class Student {

        public string name;

    }

    public static void Main()

    {

        var stuf1 = new List<Student> {new Student() {name="12"}};

        var stuf2 = new List<Student> {new Student() {name="12"}};

        var result = stuf1.Intersect(stuf2);

        Console.Write("{0}", result.Count());

    }

}