《Cracking the Coding Interview》——第8章：面向对象设计——题目5

2014-04-23 18:42

题目：设计一个在线阅读系统的数据结构。

解法：这题目太大了，我的个亲娘。显然你不可能一次加载一整本书，做到单页纸加载的粒度是很必要的。为了读书的连贯效果，预取个几页也很必要。

代码：

 // 8.5 Deign a class for an online book reader system.
 #include <unordered_map>
 using namespace std;

 class BookReaderSystem {
 public:
     BookReaderSystem() {};

     // find a book by its name and read it.
     void readBook(string book_name) {
         Page page;

         if (books.find(book_name) != books.end()) {
             i = ;
             // load the book page by page
             while (page = loadPage(books[book_name], i, page)) {
                 displayPage(page);
                 ++i;
             }
         }
     };

     ~BookReaderSystem() {
         books.clear();
     };
 private:
     // the K-V database
     unordered_map<string, Book> books;
     // load one page from a book
     bool loadPage(Book &book, int page_no, Page &page);
     // display this page
     void displayPage(Page &page);
 };