Кадровый учёт

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Кадровый_учёт
{
    class Program
    {
        static void Main(string[] args)
        {
            string[] fullNameOfTheEmployee = new string[0];
            string[] employeePosition = new string[0];
            int remoteEmployeeNumber;
            bool programWork = true;

            while (programWork)
            {
                Console.WriteLine("Введите необходимую команду:\n1)Добавить досье\n2)Вывести все досье\n3)Удалить досье\n4)Поиск по фамилии\n5)Выход");

                switch (Console.ReadLine())
                {
                    case "1":
                        Console.WriteLine("Введите ФИО сотрудника");
                        fullNameOfTheEmployee = AddDossier(fullNameOfTheEmployee);
                        Console.WriteLine("Введите должность сотрудника");
                        employeePosition = AddDossier(employeePosition);

                        Console.WriteLine("Досье добавлено. Нажмите любую клавишу");
                        break;
                    case "2":
                        ShowAllDossiers(fullNameOfTheEmployee, employeePosition);
                        break;
                    case "3":
                        Console.Write("Введите номер сотрудника, которого хотите удалить досье: ");
                        remoteEmployeeNumber = Convert.ToInt32(Console.ReadLine()) - 1;

                        fullNameOfTheEmployee = DeleteEmployeeDossier(fullNameOfTheEmployee, remoteEmployeeNumber);
                        employeePosition = DeleteEmployeeDossier(employeePosition, remoteEmployeeNumber);
                        Console.WriteLine("Досье сотрудника удалено");
                        break;
                    case "4":
                        SearchByLastName(fullNameOfTheEmployee, employeePosition);
                        break;
                    case "5":
                        programWork = false;
                        break;
                    default:
                        Console.WriteLine("Комманды под данным номером не существует. Повторите ввод команды");
                        break;
                }
                Console.ReadKey();
                Console.Clear();
            }
        }

        static string[] AddDossier(string[] expandingTheRequiredArray)
        {
            string[] expansionOfTheDossier = new string[expandingTheRequiredArray.Length + 1];
            for (int i = 0; i < expandingTheRequiredArray.Length; i++)
            {
                expansionOfTheDossier[i] = expandingTheRequiredArray[i];
            }
            expansionOfTheDossier[expansionOfTheDossier.Length - 1] = Console.ReadLine();
            expandingTheRequiredArray = expansionOfTheDossier;

            return expandingTheRequiredArray;
        }

        static void ShowAllDossiers(string[] fullNameOfTheEmployee, string[] employeePosition)
        {
            for (int i = 0; i < fullNameOfTheEmployee.Length; i++)
            {
                Console.Write(i + 1 + ")" + fullNameOfTheEmployee[i] + " - " + employeePosition[i] + "; ");
            }
        }

        static void SearchByLastName(string[] fullNameOfTheEmployee, string[] employeePosition)
        {
            string userEnteredLastName;

            Console.WriteLine("Введите фамилию сотрудника");
            userEnteredLastName = Console.ReadLine();

            for (int i = 0; i < fullNameOfTheEmployee.Length; i++)
            {
                if (fullNameOfTheEmployee[i].Contains(userEnteredLastName))
                {
                    Console.WriteLine("Досье сотрудника найдено\n" + (i + 1) + fullNameOfTheEmployee[i] + " - " + employeePosition[i]);
                }
                else
                {
                    Console.WriteLine("Данный сотрудник не найден");
                }
                break;
            }
        }

        static string[] DeleteEmployeeDossier(string[] theArrayInWhichTheDossierIsDeleted, int remoteEmployeeNumber)
        {
            string[] newArray = new string[theArrayInWhichTheDossierIsDeleted.Length - 1];
            for (int i = 0; i < remoteEmployeeNumber; i++)
            {
                newArray[i] = theArrayInWhichTheDossierIsDeleted[i];
            }

            for (int i = remoteEmployeeNumber + 1; i < theArrayInWhichTheDossierIsDeleted.Length; i++)
            {
                newArray[i - 1] = theArrayInWhichTheDossierIsDeleted[i];
            }

            theArrayInWhichTheDossierIsDeleted = newArray;

            return theArrayInWhichTheDossierIsDeleted;
        }
    }
}