using System;

using System.Linq;

using System.Collections.Generic;

​

public class Student

{

    public string FirstName

    { get; set; }

    public string LastName

    { get; set; }

    public int Age

    { get; set; }

    public Student(string firstName, string lastName, int age)

    {

        this.FirstName = firstName;

        this.LastName = lastName;

        this.Age = age;

    }

    public static void ExtractNamesBeforeSurnames(Student[] students)

    {

        var firstNameBeforeLast =

            from student in students

            where student.FirstName[0] < student.LastName[0]

            select student;

        foreach (Student student in firstNameBeforeLast)

        {

            Console.WriteLine(student.FirstName + " " + student.LastName);

        }

    }

}

public class Program

{

    public static void Main()

    {

        Student[] array = new Student[] 

        {

            new Student("Mark", "Marky", 16),

            new Student("Daniel", "Wacko", 17),

            new Student("Stan", "Masterson", 15),

            new Student("Michell", "Qthilson", 18),

        };

        Student.ExtractNamesBeforeSurnames(array);

    }

}

​

/*Write a class Student with the following properties: first name, last name

and age. Write a method that for a given array of students finds those,

whose first name is before their last one in alphabetical order. Use LINQ.*/