ДЗ: Кадры

using System;

namespace Kadr
{
    class Program
    {
        static void Main(string[] args)
        {
            const string CommandAdd = "add";
            const string CommandPrint = "print";
            const string CommandDelete = "delete";
            const string CommandFind = "find";
            const string CommandExit = "exit";

            string[] fullNames = new string[0];
            string[] positions = new string[0];
            string userInput;
            bool isRunning = true;

            while (isRunning)
            {
                Console.Clear();
                Console.WriteLine($"{CommandAdd} - добавить досье\n{CommandPrint} - распечатать досье\n{CommandDelete} - удалить досье");
                Console.WriteLine($"{CommandFind} - найти номер досье по фамилии\n{CommandExit} - выйти из программы");
                Console.WriteLine();
                userInput = Console.ReadLine();

                switch (userInput)
                {
                    case CommandAdd:
                        AddFile(ref fullNames, ref positions);
                        break;

                    case CommandPrint:
                        PrintFiles(fullNames, positions);
                        break;

                    case CommandDelete:
                        DeleteFile(ref fullNames, ref positions);
                        break;

                    case CommandFind:
                        FindFiles(fullNames, positions);
                        break;

                    case CommandExit:
                        isRunning = false;
                        break;
                }
            }
        }

        static void AddFile(ref string[] fullNames, ref string[] positions)
        {
            string fullName;
            string position;

            Console.WriteLine("Введите ФИО");
            fullName = Console.ReadLine();
            Console.WriteLine("Введите должность");
            position = Console.ReadLine();
            fullNames = AddInArray(fullNames, fullName);
            positions = AddInArray(positions, position);
            Console.WriteLine("Количество досье в архиве: " + fullNames.Length);
            Console.ReadKey();
        }

        static void PrintFiles(string[] fullNames, string[] positions)
        {
            if (fullNames.Length == 0)
            {
                Console.WriteLine("В досье отсутствуют записи");
            }
            else
            {
                for (int i = 0; i < fullNames.Length; i++)
                    Console.WriteLine($"{i + 1} - {fullNames[i]} - {positions[i]}");
            }

            Console.ReadKey();
        }

        static void DeleteFile(ref string[] fullNames, ref string[] positions)
        {
            Console.Write("Введите номер удаляемой записи ");
            int fileIndex = Convert.ToInt32(Console.ReadLine()) - 1;

            if (fileIndex >= fullNames.Length)
            {
                Console.WriteLine("Досье с данным номером отсутствует");
            }
            else
            {
                fullNames = DeleteFromArray(fullNames, fileIndex);
                positions = DeleteFromArray(positions, fileIndex);
            }

            Console.WriteLine("Количество досье в архиве: " + fullNames.Length);
            Console.ReadKey();
        }

        static void FindFiles(string[] fullNames, string[] positions)
        {
            Console.Write("Введите искомую фамилию ");
            string surnameRequest = Console.ReadLine();
            string foundEntries = "";
            int foundEntryCount = 0;

            for (int i = 0; i < fullNames.Length; i++)
            {
                string surname = fullNames[i].Split(' ')[0];

                if (surnameRequest == surname)
                {
                    foundEntryCount++;
                    foundEntries += string.Format($"{i} ");
                }
            }

            if (foundEntryCount == 0)
            {
                Console.WriteLine("Досье отсутствует");
            }
            else
            {
                Console.WriteLine("Фамилия встречается в досье: " + foundEntries);
            }

            Console.ReadKey();
        }

        static string[] AddInArray(string[] array, string value)
        {
            string[] temporaryArray = new string[array.Length + 1];

            for (int i = 0; i < array.Length; i++)
            {
                temporaryArray[i] = array[i];
            }

            temporaryArray[array.Length] = value;
            return temporaryArray;
        }

        static string[] DeleteFromArray(string[] array, int index)
        {
            if(array.Length == 0)
            {
                return array;
            }

            string[] temporaryArray = new string[array.Length - 1];

            for (int i = 0; i < index; i++)
            {
                temporaryArray[i] = array[i];
            }

            for (int i = index; i < temporaryArray.Length; i++)
            {
                temporaryArray[i] = array[i + 1];
            }

            return temporaryArray;
        }
    }
}