using System;

public class Program

{

    public static void Main()

    {

        int[] arr = new int[]{4,2,3,1,5,3};

        Employee[] employees = new Employee[] { new Employee("John", 21), new Employee("Bob", 31), new Employee("Mary", 25)};

        Console.WriteLine("Welcome to inbuilt sort in C#");

        //method 1:Use Sort method of Array class and pass the arr of any primitive type, int here

        Array.Sort(arr); 

        //printing

        Console.WriteLine("Primitive type array after sorting:");

        foreach(int item in arr){

            Console.Write(item + ", ");

        }

        //method 2:Use Sort method of Array class and pass the arr of any complexe type, also need to either pass delegate

        //or we can implement IComparable and implement CompareTo method.

        Array.Sort(employees); 

        //printing

        Console.WriteLine("\n Complex type array after sorting by Name using IComparable:");

        foreach(Employee item in employees){

            Console.Write(item.Name + ", ");

        }

        //method 3

        Array.Sort(employees, CustomCompareEmployee);

        //printing

        Console.WriteLine("\n Complex type array after sorting by Age using delegate:");

        foreach(Employee item in employees){

            Console.Write(item.Name + ", ");

        }

    }

    //Complex data type employee implementing IComparable to provide custom comparison

    public class Employee: IComparable{

        public string Name { get; set;}

        public int Age { get; set;}

        //constructor

        public Employee(string name, int age){

            this.Name = name;

            this.Age = age;

        }

        //implementation of CompareTo, sorting by name asc

        public int CompareTo(object employee2){

            return this.Name.CompareTo(((Employee)(employee2)).Name);

        }

    }

    //Custom sort method for method 3, sorting by age asc

    public static int CustomCompareEmployee(Employee employee1, Employee employee2){

        return employee1.Age.CompareTo(employee2.Age);

    }

}

​