using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace TestConsoleApp { internal class StackBooksOfArray { private Book[] arrayBooks = new Book[1000]; private int lenght = 0; public Book pop() { lenght--; return arrayBooks[lenght]; } public void push(Book newBook) { arrayBooks[lenght] = newBook; lenght++; } public void sort() { } } }