YdYMTdjC

1public class Foo1
2    {
3        public static async Task RunAsync()
4        {
5            var clients =await GetClients();
6            int activeCount = 0,inactiveCount=0;
7            var sw=new Stopwatch();
8            foreach (var client in clients)
9            {
10                if (client.IsActive)
11                    activeCount++;
12                else
13                    inactiveCount++;
14            }
15            Console.WriteLine($"Найдено {clients.Count} клиентов. Активных {activeCount}, неактивных {inactiveCount}");
16            var appropriateClients = new List<Client>();
17            foreach (var client in clients)
18            {
19                if(client.IsActive&&IsAppropriateEmail(client))
20                    appropriateClients.Add(client);
21            }
22
23            Console.WriteLine($"Найдено {appropriateClients.Count}");
24            Console.ReadLine();
25        }
26
27        private static bool IsAppropriateEmail(Client client)
28        {
29            return client.Email.EndsWith(".ru");
30        }
31
32        private static async Task<List<Client>> GetClients()
33        {
34            //TODO: получать данных из БД
35            var result = new List<Client>();
36            for (int i = 1; i <= 10000000; i++)
37            {
38                var client = new Client
39                {
40                    Name = "клиент " + i,
41                    IsActive = i % 2 == 0 || i % 5 == 0
42                };
43
44                string domain = "yandex.ru";
45                if (i % 3 == 0)
46                {
47                    domain = "gmail.com";
48                }
49                else if (i % 5 == 0)
50                {
51                    domain = "mail.ru";
52                }
53                else if (i % 9 == 0)
54                {
55                    domain = "yandex.ua";
56                }
57                else if (i % 11 == 0)
58                {
59                    domain = "yandex.kz";
60                }
61
62                client.Email = $"client{i}@{domain}";
63                result.Add(client);
64            }
65            return result;
66        }
67
68        public class Client
69        {
70            public string Name { get; set; }
71
72            public string Email { get; set; }
73
74            public bool IsActive { get; set; }
75        }
76    }