using System;
using System.Collections.Generic;
using System.Linq;

namespace MyCompiler {
    class Student{
        public int StudentID;
        public string StudentName;
        public int Age;
    }
    class Program  {
        public static void Main(string[] args) {
            Console.WriteLine("Hello world!");
            IList<Student> studentList = new List<Student>() { 
                new Student() { StudentID = 1, StudentName = "John",  Age= 13} ,
                new Student() { StudentID = 2, StudentName = "Moin",  Age = 21 } ,
                new Student() { StudentID = 3, StudentName = "Bill",  Age = 13 } ,
                new Student() { StudentID = 4, StudentName = "Ram" , Age = 20} ,
                new Student() { StudentID = 5, StudentName = "Ron" , Age = 15 } 
            };
            var filterlist = from item in studentList
                             where item.Age > 12
                             select item.StudentName;
            Console.WriteLine(String.Join(",",filterlist));

            //ORDER BY
            var filterlistOB = from item in studentList
                               orderby item.StudentName, item.Age descending
                               select new {item.StudentName,item.Age};
            Console.WriteLine(String.Join(",\n",filterlistOB));

            //GROUP BY 
            var filterlistGB =  from item in studentList
                                group item by item.Age;
            foreach(var ele in filterlistGB){
                Console.WriteLine("Key is {0} ",ele.Key);    
                //each group has the colelction of other properties within
                foreach(Student s in ele){
                    Console.WriteLine("Name of the student {0} ",s.StudentName);        
                }
            }


            //JOIN 
            IList<Standard> standardList = new List<Standard>() { 
                new Standard(){ StandardID = 1, StandardName="Standard 1"},
                new Standard(){ StandardID = 2, StandardName="Standard 2"},
                new Standard(){ StandardID = 3, StandardName="Standard 3"}
            };

            
            
        }
    }
}