using System;

using System.Linq;

public class Program

{

    public static void countries(){

        String[] data = {"India","Europe","Sri Lanka","America","Russia","Columbia","Australia","China"};

        var result = from country in data where country.Length<=6 orderby country ascending select country;

        foreach(String item in result){

            Console.WriteLine(item);

        }

    }

    public static void cities(){

        String[] data = {"Hyderabad","Sydney","Egypt","New York","California","Sen Francisco","Mexico","Rome"};

        var result = from city in data group city by city.Substring(0,1) into cityGroup select cityGroup;

        foreach(var item in result){

                Console.WriteLine(item.Key);

            foreach(var item2 in item){

                    Console.WriteLine(item2);

            }

        }

    }

    public static void Main()

    {

        Program.cities();

    }

}