Поиск в строке
С помощью метода IndexOf мы можем определить индекс первого вхождения отдельного символа или подстроки в строке.
Подобным образом действует метод LastIndexOf, только находит индекс последнего вхождения символа или подстроки в строку.
BY Библиотека задач по C# | тесты, код, задания
Mr. Durov launched Telegram in late 2013 with his brother, Nikolai, just months before he was pushed out of VK, the Russian social-media platform he founded. Mr. Durov pitched his new app—funded with the proceeds from the VK sale—less as a business than as a way for people to send messages while avoiding government surveillance and censorship.
Secret Chats are one of the service’s additional security features; it allows messages to be sent with client-to-client encryption. This setup means that, unlike regular messages, these secret messages can only be accessed from the device’s that initiated and accepted the chat. Additionally, Telegram notes that secret chats leave no trace on the company’s services and offer a self-destruct timer.
Библиотека задач по C | тесты код задания from ca