View difference between Paste ID: QyiqkK3G and C26sWULh

 using System;
 using System.Collections.Generic;
-namespace C_sharp_Light
+using System.Linq;
 
 namespace LinqTrain
 {
-        static void Main(string[] args)
+
     {
-
+        public static void Main()
         {
             new Hospital().Work();
         }
     }
     public static class RandomStatic
     {
         static private Random _rand = new Random();
         static public int GetNext(int min, int max)
         {
             return _rand.Next(min, max);
         }
     }
     class FullName
     {
         public string Name { get; private set; }
         public string Surname { get; private set; }
         public string Patronymic { get; private set; }
         public FullName()
         {
             Name = new string[] { "Август", "Богдан", "Ваня", "Георгий", "Данил", "Женя" }[RandomStatic.GetNext(0, 6)];
             Surname = new string[] { "ЛУчников", "Захарчев", "Зайцев", "КУзнецов", "Столяров", "Коробничиков" }[RandomStatic.GetNext(0, 6)];
             Patronymic = new string[] { "Сергеевич", "Андреевич", "Саавич", "Арсеневич" }[RandomStatic.GetNext(0, 4)];
         }
         public string GetInfo()
         {
             return $"{Surname} {Name} {Patronymic}:";
         }
     }
     class Hospital
     {
         private List<Patient> _patients = new List<Patient>();
         public Hospital()
         {
             for (int i = 0; i < 30; i++)
             {
                 _patients.Add(new Patient());
             }
         }
         public void Work()
         {
             bool isOpen = true;
             while (isOpen)
             {
                 Console.Clear();
                 Console.WriteLine("1 - Сортировка и вывод пациентов по ФИО \n2 - сортировка и вывод пациентов по возрасту \n3 - вывод пациентов по болезни");
                 switch (Console.ReadKey().Key)
                 {
                     case ConsoleKey.D1:
                         SortByFullName();
                         break;
                     case ConsoleKey.D2:
                         SortByAge();
                         break;
                     case ConsoleKey.D3:
                         SortByDisease();
                         break;
                     case ConsoleKey.Escape:
                         isOpen = false;
                         break;
                 }
             }
         }
         private void SortByFullName()
         {
             Console.Clear();
             List<Patient> sortList = _patients.OrderBy(patients => patients.FullName.GetInfo()).ToList<Patient>();
             int count = 0;
             foreach (var item in sortList)
             {
                 Console.WriteLine($"{count}: {item.GetInfo()}");
                 count++;
             }
             Console.ReadKey();
         }
         private void SortByAge()
         {
             Console.Clear();
             var sortList = _patients.OrderBy(patients => patients.Age);
             int count = 0;
             foreach (var item in sortList)
             {
                 Console.WriteLine($"{count}: {item.GetInfo()}");
                 count++;
             }
             Console.ReadKey();
         }
         private void SortByDisease()
         {
             Console.Clear();
             Console.Write("Введите название болезни: ");
             string disease = Console.ReadLine();
             var sortList = _patients.Where(patient => patient.Disease.ToLower() == disease.ToLower());
             int count = 0;
             foreach (var item in sortList)
             {
                 Console.WriteLine($"{count}: {item.GetInfo()}");
                 count++;
             }
             Console.ReadKey();
         }
     }
     class Patient
     {
         public FullName FullName { get; private set; }
         public int Age { get; private set; }
         public string Disease { get; private set; }
 
         public Patient()
         {
             FullName = new FullName();
             Disease = new string[] { "ОРВИ", "Грипп", "Пнемония", "Ковид", "Перелом" }[RandomStatic.GetNext(0, 5)];
             Age = RandomStatic.GetNext(5, 75);
         }
         public string GetInfo()
         {
             return $"{FullName.GetInfo()} Возраст={Age}; Заболевание={Disease}";
         }
     }
 }