C# LIST

///////////////////////////////////////////////////////////////////////////  ne povtarqsti se elementi v list      ///////////////////////////////////////

            List<int> k = new List<int>() {1,2,3,4,5,6,7,8,8,9,11,10,11,12,13 };
            List<int> kuk = new List<int>() {1,2,3,4,5,9,13,14,15,16,16,15 };

            List<int> firstList = new List<int>();

            firstList.AddRange(k);
            firstList.AddRange(kuk);

            firstList.Sort();
            Int32 index = 0;

            for (int i = 0; i < k.Count + kuk.Count -1; i++)
            {
                if (firstList[index] == firstList[index + 1])
                    firstList.RemoveAt(index);
                else
                {
                    index++;
                }

            }

            for (int i = 0; i < firstList.Count; i++)
            {
                Console.WriteLine(firstList[i]);
            }





/////////////////////////////////////////////////////////////////////
string allLangs = "C#, Java; HTML, CSS; PHP, JavaScript; SQL";
            string[] langs = allLangs.Split(new char[] { ',', ';', ' ' },
                StringSplitOptions.RemoveEmptyEntries);

            List<string> lst1 = langs.OfType<string>().ToList();

            for (int i = 0; i < lst1.Count; i++)
            {
                if (i == lst1.Count - 1)
                {
                    Console.Write(lst1[i]);
                }
                else
                {
                    Console.Write(lst1[i] + ", ");
                }
            }




            /////////////////////////////////////////////////////////
            List<string> myStrings = new List<string> { "ours", "mine", "yours" };
            string joinedString = string.Join(", ", myStrings);
            string[] a = joinedString.Select(c => c.ToString()).ToArray();

            List<string> lst = a.OfType<string>().ToList();
            //lst.AddRange(a);
            List<string> names = new List<string>();
            names.AddRange(a);



            foreach (var name in lst)
            {
                Console.Write(name);
            }
            Console.WriteLine();

            foreach (var nam in names)
            {
                Console.Write(nam);
            }
            Console.WriteLine();





///////  list string  /////

          string[] input = { "four", "five", "six" };
            List<string> names = new List<string>() { "Peter", "Maria", "Katya", "Todor","Maria","Dragan","Petkan","Grozdan","Monika","Maria" };
            names.Add("Nakov"); // Peter, Maria, Katya, Todor, Nakov
            names.RemoveAt(0); // Maria, Katya, Todor, Nakov
            names.Remove("Maria");
            names.RemoveAll(item => item == "Maria");
            names.RemoveRange(0, 3);
            names.Insert(3, "Sylvia"); // Maria, Katya, Todor, Sylvia, Nakov
            names[1] = "Michael"; // Maria, Michael, Todor, Sylvia, Nakov
            names.Add("kondio");
            names.AddRange(input);
            names.Sort();

            foreach (var name in names)
            {
                Console.WriteLine(name);
            }


////// list  numbers ////////

List<int> numbers = new List<int>();
        numbers.Add(5);
        Console.WriteLine(numbers[0]); // 5

        Console.WriteLine();

        for (int i = 2; i <= 20; i+=2)
        {
            numbers.Add(i);
        }

        numbers.Sort();

        for (int i = 0; i < numbers.Count; i++)
        {
            Console.WriteLine(numbers[i]);
        }

/// list ot listove //////////////////////

List<List<string>> myList = new List<List<string>>();
myList.Add(new List<string> { "a", "b" });
myList.Add(new List<string> { "c", "d", "e" });
myList.Add(new List<string> { "qwerty", "asdf", "zxcv" });
myList.Add(new List<string> { "a", "b" });

// To iterate over it.
foreach (List<string> subList in myList)
{
    foreach (string item in subList)
    {
        Console.WriteLine(item);
    }
}

/////////////////////////////////////////////////////////////////////////// fukncii  na list

List<string> listOfStrings = new List<string>();
            string[] arrayOfStrings = { "Pesho", "Ivan", "Dobri", "Gosho","albania","armenia" };
            listOfStrings.AddRange(arrayOfStrings);
            listOfStrings.AddRange(new string[]{"kilata","madafaka","pulna","Gosho"});

            listOfStrings.RemoveAll(x => x == "Gosho");

          //  foreach (string str in arrayOfStrings)
          //  {
           //     listOfStrings.Add(str);
          //  }

            Console.WriteLine("Using \"foreach\" loop to traverse the List");
            Console.WriteLine(new string('-', 20));
            foreach (string str in listOfStrings)
            {
                Console.WriteLine(str);
            }

            Console.WriteLine(new string('-', 50));
            Console.WriteLine("Using \"for\" loop to traverse the List");
            Console.WriteLine(new string('-', 20));
            for (int i = 0; i < listOfStrings.Count; i++)
            {
                Console.WriteLine("{0}={1}", i ,listOfStrings[i]);
            }

            Console.WriteLine();

            Console.WriteLine(listOfStrings.Contains("kilata"));
            Console.WriteLine(listOfStrings.Count);
            Console.WriteLine(listOfStrings.IndexOf("kilata"));
            //////////////////
            listOfStrings.Reverse();
            listOfStrings = listOfStrings.OrderBy(x => x.Length).ToList();// podrejda po duljina na elementite

            listOfStrings = listOfStrings.Where(x => x[0]== 'a').ToList();// vzima elementite koit zapo4vat s 'a'
            foreach (string str in listOfStrings)
            {
                Console.WriteLine(str);
            }
            listOfStrings.ToArray();


/////////////////////////////////////////////////// capacitet na list

List<int> list = new List<int>();
        int n = int.Parse(Console.ReadLine());

        string lineBreak = new string('-', 20);

        for (int i = 0; i < n + 1; i++)
        {
            var capacity = list.Capacity;
            var count = list.Count;
            Console.WriteLine("Total Capacity of the List: {0}\nused:{1}\n{2}",
                capacity, count, lineBreak);
            list.Add(i);
        }



//// /////////////////////////////////   simetrichen list //////////////////////////////////////////


 List<int> listOfStrings = new List<int>{1,2,3,2,1};

            bool isSymmetric = false;
            for (int i = 0; i < listOfStrings.Count / 2; i++)// na purvoto zavurtane na cikula size = 5 i za tova 5 - 0 - 1 = 4 index koito mi e 1 v slu4aq
            {                                         // pri vtoroto zavurtane mi vzima 1 i 3 element i taka natatuk
                if (listOfStrings[i] == listOfStrings[listOfStrings.Count - i - 1])
                {
                    isSymmetric = true;
                    break;
                }
            }

            Console.WriteLine("Symmetric? --> {0}", isSymmetric);


/////////////////////////////  stoinosti ot list v masiv v drug 2 list  ///////////////////////////////////////////

            List<int> listOfStrings = new List<int> { 1, 2, 3, 4, 5 };
            int[] arr2 = new int[listOfStrings.Count];
            //List<int> listOfStrings12 = new List<int>(arr2.Length);

            for (int i = 0; i < listOfStrings.Count; i++)
            {
                arr2[i] = listOfStrings[i] * listOfStrings[i];
            }

            List<int> listOfStrings12 = new List<int>();
            listOfStrings12.AddRange(arr2);

            //////// reversvane na masiv 2 variant
            Console.WriteLine();
            for (int i = listOfStrings12.Count - 1; i > -1; i--)
            {
                Console.Write("arr = {0} ", listOfStrings12[i]);

            }
            Console.WriteLine();


 ///////////////////// umnojenie na masiv  //////////////////////////////////////////////////////////


List<int> listOfStrings = new List<int> { 1, 2, 3, 4, 5 };
            int[] arr3 = new int[listOfStrings.Count -1];
            //List<int> listOfStrings12 = new List<int>(arr2.Length);

            for (int i = 0; i < listOfStrings.Count - 1; i++)
            {
                arr3[i] = listOfStrings[i] * listOfStrings[i + 1];
            }

            List<int> listOfStrings12 = new List<int>();
            listOfStrings12.AddRange(arr3);

            //////// reversvane na masiv 2 variant
            Console.WriteLine();
            for (int i = listOfStrings12.Count - 1; i > -1; i--)
            {
                Console.Write("arr = {0} ", listOfStrings12[i]);

            }
            Console.WriteLine();





///////////////////// add s console.readLine ////////////////////////////////////////


 List<int> listOfStrings = new List<int>();

            for (int i = 0; i < 5; i++)
            {
                Console.WriteLine("Please enter a number");
                listOfStrings.Add(int.Parse(Console.ReadLine())); // HERE !!
            }


            List<int> list = new List<int>();

            for (int i = 0; i < 5; i++)
            {
                Console.WriteLine("Please enter a number");
                list.Add(int.Parse(Console.ReadLine())); // HERE !!
            }


            if (list.Count != listOfStrings.Count)
            {
                Console.WriteLine("Error! The FIRST Array lenght and the SECOND Array lenght are not equal. Please try again and enter EQUAL array lenghts");
            }


            bool areEqual = true;
            for (int i = 0; i < list.Count; i++)
            {
                if (list[i] != listOfStrings[i])
                {
                    areEqual = false;
                    break;
                }
            }

            Console.WriteLine("The two arrays are equal: {0}", areEqual);


/////////////////////////////   add drug nachin i list .join   //////////////////////



List<double> items = new List<double>();
  for (double i = 0; i < 10; i++)
  {
       string userInput;
       double newItem;

       // repeatedly ask for input from the user until it's a valid double
       do
       {
           Console.Write(string.Format("Enter item #{0}: ", i));
           // read from console into userInput
           userInput = Console.ReadLine();
       } while (!double.TryParse(userInput, out newItem));

       // add the new item to the array
       items.Add(newItem);
  }

  // output all the items to the console, separated by commas
  Console.WriteLine(
      string.Join(", ",
          items.Select(item => item.ToString())
      )
  );



//////////////////


///////////////////////////// HOMEWORK  za array no prepraveno kato list  ////////////////////////////////////


Problem 4. Maximal sequence //////////////////////////////////////////

static int bestLength = 0;
     static int bestElement = 0;

        static void Main()
        {


            string[] STRnumbers = Console.ReadLine().Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);

            int[] nums = new int[STRnumbers.Length];
            nums = Array.ConvertAll<string, int>(STRnumbers, int.Parse);

            List<int> listOfStrings = nums.OfType<int>().ToList();

                FindBestSequence(listOfStrings);
                string kurr = string.Join(". ", listOfStrings);

                Console.Write("The maximal sequence of equal elements in the array is: {");
                for (int i = 0; i < bestLength; i++)
                {
                        Console.Write(i != bestLength - 1 ? bestElement + ", " : bestElement + "}\n");
                }
        }


        private static void FindBestSequence(List<int> nums)
        {
        int currLength = 1;
        int currElement = nums[0];

                if (nums.Count == 1)
                {
                        bestElement = currElement;
                        bestLength = 1;
                        return;
                }

                for (int i = 1; i < nums.Count; i++)
                {
                        if (nums[i] == currElement)
                        {
                                currLength++;
                        }
                        else
                        {
                                currElement = nums[i];
                                currLength = 1;
                        }

                        if (currLength >= bestLength)
                        {
                                bestLength = currLength;
                                bestElement = currElement;
                        }
                }



5 zadacha prosot smenqme vhoda za da e list kato v 4 zadacha



9 zadacha nai-mnogo povtarqshto se chislo v lista //////////////////////////////////////////


string[] STRnumbers = Console.ReadLine().Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);

            int[] nums = new int[STRnumbers.Length];
            nums = Array.ConvertAll<string, int>(STRnumbers, int.Parse);

            List<int> names = nums.OfType<int>().ToList();



            int[] input = {1,2,3,4,5};
            names.Add(666); // Peter, Maria, Katya, Todor, Nakov
            names.RemoveAt(0); // Maria, Katya, Todor, Nakov
            names.Remove(777);
            names.RemoveAll(item => item == 4);
            names.RemoveRange(0, 3);
            names.Insert(3, 6); // Maria, Katya, Todor, Sylvia, Nakov
            names[1] = 88; // Maria, Michael, Todor, Sylvia, Nakov

            names.AddRange(input);

            var most = names.GroupBy(i => i).OrderByDescending(grp => grp.Count())
            .Select(grp => grp.Key).First();

            names.Sort();


            names.RemoveAt(0);

            Console.WriteLine(most);