【正文】 。using std::cin。 // add amount to balance} // end function credit// debit (subtract) an amount from the account balancevoid Account::debit( int amount ){ if ( amount balance ) // debit amount exceeds balance cout Debit amount exceeded account balance.\n endl。 // assume that the balance begins at 0 // if initialBalance is greater than 0, set this value as the // balance of the Account。 // data member that stores the balance}。 // constructor initializes balance void credit( int )。 // display wele message and instructor39。 pass a course name and instructor name GradeBook gradeBook( CS101 Introduction to C++ Programming, Professor Smith )。s name cout This course is presented by: getInstructorName() endl。 // store the instructor name} // end function setInstructorName// function to retrieve the instructor namestring GradeBook::getInstructorName(){ return instructorName。 // initializes courseName setInstructorName( instructor )。 // instructor name for this GradeBook}。 // function to set instructor name string getInstructorName()。class GradeBook{public: // constructor initializes course name and instructor name GradeBook( string, string )。 void setCourseName( string )。 // function to retrieve instructor name void displayMessage()。 // end class GradeBook類成員函數(shù)：include iostreamusing std::cout。 // initialiZes instructorName} // end GradeBook constructor// function to set the course namevoid GradeBook::setCourseName( string name ){ courseName = name。} // end function getInstructorName// display a wele message and the instructor39。} // end function displayMessage測試文件：include iostreamusing std::cout。 // display initial value of instructorName of GradeBook object cout gradeBook instructor name is: () \n\n。s name ()。 // add an amount to the account balance void debit( int )。 // end class Account類成員函數(shù)：include iostreamusing std::cout。 otherwise, balance remains 0 if ( initialBalance 0 ) balance = initialBalance。 if ( amount = balance ) // debit amount does not exceed balance balance = balance amount。using std::endl。 cout account2 balance: $ () endl。 // obtain user input cout \nattempting to subtract withdrawalAmount from account1 balance\n\n。 cout \nEnter withdrawal amount for account2: 。 // try to subtract from account2 // display balances cout account1 balance: $ () endl。// Invoice class definitionclass Invoice{public: // constructor initializes the four data members Invoice( string, string, int, int )。 // part description string getPartDescription()。 // price per item int getPricePerItem()。 // description of the part being sold int quantity。using std::endl。 // store partDescription setQuantity( count )。} // end function getPartNumber// set part descriptionvoid Invoice::setPartDescription( string description ){ partDescription = description。 // set quantity to count if ( count = 0 ) // if quantity is not positive { quantity = 0。 if not positive, set to 0void Invoice::setPricePerItem( int price ){ if ( price 0 ) // if price is positive pricePerItem = price。} // end function getPricePerItem// calulates invoice amount by multiplying quantity x price per itemint Invoice::getInvoiceAmount(){ return getQuantity() * getPricePerItem()。// include definition of class Invoice from include // function main begins program executionint main(){ // create an Invoice object Invoice invoice( 12345, Hammer, 100, 5 )。 cout Price per item: $ () endl。 ( 5 )。 cout Part description: () endl。 return 0。 // set first name string getFirstName()。 // set weekly salary int getMonthlySalary()。 // Employee39。 // end class Employee類成員函數(shù)：include iostreamusing std::cout。 // validate and store monthly salary} // end Employee constructor// set first namevoid Employee::setFirstName( string name ){ firstName = name。} // end function getLastName// set monthly salary。} // end function getMonthlySalary測試函數(shù)：include iostreamusing std::cout。 // display each Employee39。s monthly salary multiplied by 12 int monthlySalary1 = ()。 cout () () : $ monthlySalary2 * 12 endl。s yearly salary again cout \nEmployees39。 cout () () : $ monthlySalary1 * 12 endl。 // indicate successful termination} // end main類定義：class Date {public: Date( int, int, int )。 // set day int getDay()。 // displays date in mm/dd/yyyy formatprivate: int month。 // end class Date類成員函數(shù)：include iostreamusing std::cout。 setDay( d )。 if ( month 12 ) month = 1。} // end function getDay// set yearvoid Date::setYear( int y ){ year = y。 day 39。using std::endl。 cout Year: () endl。 // invalid month ( 1 )。 // output the modified date (1/1/2005) return 0。 // function add Complex subtract( const Complex amp。 // set plex number private: double realPart。 include Complex::Complex( double real, double imaginary ){ setComplexNumber( real, imaginary )。right ){ return Complex( realPart , imaginaryPart )。)39。 using std::endl。 ()。 // output object c cout 39。 // and imaginaryPart ()。 c = ( b )。} // end main類定義：ifndef RATIONAL_Hdefine RATIONAL_Hclass Rational {public: Rational( int = 0, int = 1 )。 )。 )。 // integer numerator int denominator。 include // include definition of class RationalRational::Rational( int n, int d ){ numerator = n。a ){ Rational t。 ()。 // creates Rational object = * numerator。 // store the fraction in reduced form return t。 = *