using System;

using System.Linq;

using System.Collections.Generic;

​

public class Program

{

    public class PersonComparer : IEqualityComparer<Person>

    {

        public bool Equals(Person x, Person y)

        {

            return x.Name == y.Name;

        }

        public int GetHashCode(Person obj)

        {

            return obj.GetHashCode();

        }

    }

    public class Person

    {

        public string Name {get; set;}

        public int Age {get; set;}

    }

​

    public static List<Person> people = new List<Person>

        {

            new Person

            {

                Name = "Pippo Franco",

                Age = 81

            },

            new Person

            {

                Name = "Pippo Baudo",

                Age = 85,

            },

            new Person

            {

                Name = "Massimo Boldi",

                Age = 76,

            },

            new Person

            {

                Name = "Giancarlo Magalli",

                Age = 74,

            },

            new Person

            {

                Name = "Barbara D'Urso",

                Age = 64,

            }

        };

    public static void Main()

    {

        Console.WriteLine("Quantifier example.\n");

        bool result = people.All(p => p.Age > 60);

        Console.WriteLine("All:");

        Console.WriteLine(result);

        Console.WriteLine();

        result = people.Any(p => p.Age < 60);

        Console.WriteLine("Any:");

        Console.WriteLine(result);

        Console.WriteLine();

        result = people

            .Select(p => p.Name)

            .Contains("Massimo Boldi");

        Console.WriteLine("Contains:");

        Console.WriteLine(result);

        Console.WriteLine();

        result = people.Contains(new Person

            { 

                Name = "Massimo Boldi", 

                Age = 76 

             });

        Console.WriteLine("Contains (IEqualityComparer):");

        Console.WriteLine(result);

        Console.WriteLine();

    }

}