1   // Fig. 5.9: GradeBook.h
 2   // GradeBook class definition that counts letter grades.
 3   // Member functions are defined in GradeBook.cpp
 4   #include <string> // program uses C++ standard string class
 5
 6   // GradeBook class definition
 7   class GradeBook
 8   {
 9   public:
10      explicit GradeBook( std::string ); // initialize course name
11      void setCourseName( std::string ); // set the course name
12      std::string getCourseName() const; // retrieve the course name
13      void displayMessage() const; // display a welcome message
14      void inputGrades(); // input arbitrary number of grades from user     
15      void displayGradeReport() const; // display report based on user input
16   private:
17      std::string courseName; // course name for this GradeBook
18      unsigned int aCount; // count of A grades
19      unsigned int bCount; // count of B grades
20      unsigned int cCount; // count of C grades
21      unsigned int dCount; // count of D grades
22      unsigned int fCount; // count of F grades
23   }; // end class GradeBook

 1   // Fig. 5.10: GradeBook.cpp
 2   // Member-function definitions for class GradeBook that
 3   // uses a switch statement to count A, B, C, D and F grades.
 4   #include <iostream>
 5   #include "GradeBook.h" // include definition of class GradeBook
 6   using namespace std;
 7
 8   // constructor initializes courseName with string supplied as argument;
 9   // initializes counter data members to 0
10   GradeBook::GradeBook( string name )
11      : aCount( 0 ), // initialize count of A grades to 0
12        bCount( 0 ), // initialize count of B grades to 0
13        cCount( 0 ), // initialize count of C grades to 0
14        dCount( 0 ), // initialize count of D grades to 0
15        fCount( 0 )  // initialize count of F grades to 0
16   {
17      setCourseName( name );
18   } // end GradeBook constructor
19
20   // function to set the course name; limits name to 25 or fewer characters
21   void GradeBook::setCourseName( string name )
22   {
23      if ( name.size() <= 25 ) // if name has 25 or fewer characters
24         courseName = name; // store the course name in the object
25      else // if name is longer than 25 characters
26      { // set courseName to first 25 characters of parameter name
27         courseName = name.substr( 0, 25 ); // select first 25 characters
28         cerr << "Name "" << name << "" exceeds maximum length (25). "
29            << "Limiting courseName to first 25 characters. " << endl;
30      } // end if...else
31   } // end function setCourseName
32
33   // function to retrieve the course name
34   string GradeBook::getCourseName() const
35   {
36      return courseName;
37   } // end function getCourseName
38
39   // display a welcome message to the GradeBook user
40   void GradeBook::displayMessage() const
41   {
42      // this statement calls getCourseName to get the
43      // name of the course this GradeBook represents
44      cout << "Welcome to the grade book for " << getCourseName() << "! "
45         << endl;
46   } // end function displayMessage
47
48   // input arbitrary number of grades from user; update grade counter
49   void GradeBook::inputGrades()
50   {
51      int grade; // grade entered by user
52
53      cout << "Enter the letter grades." << endl
54         << "Enter the EOF character to end input." << endl;
55
56      // loop until user types end-of-file key sequence
57      while ( ( grade = cin.get() ) != EOF )
58      {
59         // determine which grade was entered                
60         switch ( grade ) // switch statement nested in while
61         {                                                   
62            case 'A': // grade was uppercase A               
63            case 'a': // or lowercase a                      
64               ++aCount; // increment aCount                 
65               break; // necessary to exit switch            
66                                                             
67            case 'B': // grade was uppercase B               
68            case 'b': // or lowercase b                      
69               ++bCount; // increment bCount                 
70               break; // exit switch                         
71                                                             
72            case 'C': // grade was uppercase C               
73            case 'c': // or lowercase c                      
74               ++cCount; // increment cCount                 
75               break; // exit switch                         
76                                                             
77            case 'D': // grade was uppercase D               
78            case 'd': // or lowercase d                      
79               ++dCount; // increment dCount                 
80               break; // exit switch                         
81                                                             
82            case 'F': // grade was uppercase F               
83            case 'f': // or lowercase f                      
84               ++fCount; // increment fCount                 
85               break; // exit switch                         
86                                                             
87            case ' ': // ignore newlines,                   
88            case ' ': // tabs,                              
89            case ' ': // and spaces in input                 
90               break; // exit switch                         
91                                                             
92            default: // catch all other characters           
93               cout << "Incorrect letter grade entered."     
94                  << " Enter a new grade." << endl;          
95               break; // optional; will exit switch anyway   
96         } // end switch                                     
97      } // end while
98   } // end function inputGrades
99
100  // display a report based on the grades entered by user
101  void GradeBook::displayGradeReport() const
102  {
103     // output summary of results
104     cout << " Number of students who received each letter grade:"
105        << " A: " << aCount // display number of A grades
106        << " B: " << bCount // display number of B grades
107        << " C: " << cCount // display number of C grades
108        << " D: " << dCount // display number of D grades
109        << " F: " << fCount // display number of F grades
110        << endl;
111  } // end function displayGradeReport

 1   // Fig. 5.11: fig05_11.cpp
 2   // Creating a GradeBook object and calling its member functions.
 3   #include "GradeBook.h" // include definition of class GradeBook
 4
 5   int main()
 6   {
 7      // create GradeBook object
 8      GradeBook myGradeBook( "CS101 C++ Programming" );
 9
10      myGradeBook.displayMessage(); // display welcome message
11      myGradeBook.inputGrades(); // read grades from user                
12      myGradeBook.displayGradeReport(); // display report based on grades
13   } // end main