split the ex8_4_5.cpp to ex8_04.cpp and ex8_05.cpp

1. use the book.txt of data folder
2. added ex8_06

ch08/README.md

@@ -22,3 +22,7 @@ while (cin >> i) /*  ...    */
 ```
 
 putting `cin` in an error state cause to terminate. such as `eofbit`, `failbit` and `badbit`.
+
+## [Exercise 8.4](ex8_04.cpp)
+## [Exercise 8.5](ex8_05.cpp)
+## [Exercise 8.6](ex8_06.cpp)

ch08/ex8_02.cpp

@@ -5,7 +5,7 @@
 //  Created by pezy on 11/27/14.
 //  Copyright (c) 2014 pezy. All rights reserved.
 //
-//  Test your function by calling it, passing cin as an argument
+//  @Brief  Test your function by calling it, passing cin as an argument
 
 #include <iostream>
 using std::istream;

ch08/ex8_04.cpp

@@ -0,0 +1,37 @@
+//
+//  ex8_04.cpp
+//  Exercise 8.4
+//
+//  Created by pezy on 11/9/14.
+//  Copyright (c) 2014 pezy. All rights reserved.
+//
+//  @Brief  Write a function to open a file for input and read its contents into a vector of strings, 
+//          storing each line as a separate element in the vector. 
+
+#include <fstream>
+#include <string>
+#include <vector>
+#include <iostream>
+
+using std::vector; using std::string; using std::ifstream; using std::cout; using std::endl;
+
+void ReadFileToVec(const string& fileName, vector<string>& vec)
+{
+    ifstream ifs(fileName);
+    if (ifs)
+    {
+        string buf;
+        while (std::getline(ifs, buf))
+            vec.push_back(buf);
+    }
+}
+
+int main()
+{
+    vector<string> vec;
+    ReadFileToVec("../data/book.txt", vec);
+    for (const auto &str : vec)
+        cout << str << endl;
+    return 0;
+}
+

ch08/ex8_05.cpp

@@ -0,0 +1,37 @@
+//
+//  ex8_05.cpp
+//  Exercise 8.5
+//
+//  Created by pezy on 11/9/14.
+//  Copyright (c) 2014 pezy. All rights reserved.
+//
+//  @Brief  Rewrite the previous program to store each word in a separate element.
+//  @See    ex8_04.cpp 
+
+#include <fstream>
+#include <string>
+#include <vector>
+#include <iostream>
+
+using std::vector; using std::string; using std::ifstream; using std::cout; using std::endl;
+
+void ReadFileToVec(const string& fileName, vector<string>& vec)
+{
+    ifstream ifs(fileName);
+    if (ifs)
+    {
+        string buf;
+        while (ifs >> buf)
+            vec.push_back(buf);
+    }
+}
+
+int main()
+{
+    vector<string> vec;
+    ReadFileToVec("../data/book.txt", vec);
+    for (const auto &str : vec)
+        cout << str << endl;
+    return 0;
+}
+

ch08/ex8_06.cpp

@@ -0,0 +1,47 @@
+//
+//  ex8_06.cpp
+//  Exercise 8.6
+//
+//  Created by pezy on 11/27/14.
+//  Copyright (c) 2014 pezy. All rights reserved.
+//
+//  @Brief  Rewrite the bookstore program from ¡ì7.1.1 (p.256) to read its transactions from a file. 
+//          Pass the name of the file as an argument to main (¡ì6.2.5, p.218). 
+//  @See    ex7_26.h (use the Sales_data)
+//  @Run    give a parameter: "../data/book.txt"
+//  @Output 0-201-78345-X 5 110
+//          0-201-78346-X 9 839.2 
+
+#include <fstream>
+#include <iostream>
+
+#include "../ch07/ex7_26.h"
+using std::ifstream; using std::cout; using std::endl; using std::cerr;
+
+int main(int argc, char **argv)
+{
+    ifstream input(argv[1]);
+
+    Sales_data total;
+    if (read(input, total))
+    {
+        Sales_data trans;
+        while (read(input, trans))
+        {
+            if (total.isbn() == trans.isbn())
+                total.combine(trans);
+            else
+            {
+                print(cout, total) << endl;
+                total = trans;
+            }
+        }
+        print(cout, total) << endl;
+    }
+    else
+    {
+        cerr << "No data?!" << endl;
+    }
+
+    return 0;
+}