gistfile1.txt

using System;
using System.Collections.Generic;

namespace Collections3
{
    internal class Program
    {
        static void Main(string[] args)
        {
            string commandAddEmployee = "add";
            string commandDeleteEmployee = "delete";
            string commandWriteAllEmployee = "info";

            bool isOpen = true;

            Dictionary<string, List<string>> employees = new Dictionary<string, List<string>>();

            while (isOpen)
            {
                Console.Clear();

                Console.WriteLine("Введите команду:");
                Console.WriteLine(commandAddEmployee + " - Добавить нового сотрудника.");
                Console.WriteLine(commandDeleteEmployee + " - Уволить сотрудника.");
                Console.WriteLine(commandWriteAllEmployee + " - Показать всех сотрудников.");

                string userInput = Console.ReadLine();

                if (userInput == commandAddEmployee)
                {
                    AddNewEmployee(employees);
                }
                else if (userInput == commandDeleteEmployee)
                {
                    DeleteEmployee(employees);
                }
                else if (userInput == commandWriteAllEmployee)
                {
                    WriteAllEmployees(employees);
                }

                Console.ReadKey();
            }
        }

        private static void AddNewEmployee(Dictionary<string, List<string>> employees)
        {
            Console.Clear();

            Console.Write("Введите должность сотрудника: ");
            string post = Console.ReadLine();

            Console.Write("Введите Фамилию Имя и Отчество сотрудника через пробел: ");
            string nameOfEmployee = Console.ReadLine();

            if (employees.ContainsKey(post))
            {
                employees[post].Add(nameOfEmployee);
            }
            else
            {
                employees.Add(post, new List<string>());
                employees[post].Add(nameOfEmployee);
            }
        }

        private static void WriteAllEmployees(Dictionary<string, List<string>> employees)
        {
            Console.Clear();

            foreach (var post in employees)
            {
                Console.WriteLine($"\n{post.Key}\n");

                foreach (var employee in post.Value)
                {
                    Console.WriteLine(employee);
                }
            }
        }

        private static void DeleteEmployee(Dictionary<string, List<string>> employees)
        {
            Console.Clear();

            Console.Write("Введите ФИО сотрудника которого хотите уволить: ");
            string userInput = Console.ReadLine();

            foreach (var post in employees) 
            {
                int counterIndex = post.Value.Count - 1;
                
                for (int i = counterIndex; i >= 0; i--)
                {
                    if (post.Value[i] == userInput)
                    {
                        post.Value.RemoveAt(i);
                       
                        break;
                    }
                }

                if (post.Value.Count == 0)
                {
                    employees.Remove(post.Key);
                    
                    break;
                }
            }
        }
    }
}