// Chapter 7 of C++ How to Program // Programming Challenge 12 (Solution) #include "savings.h" #include using std::cout; using std::fixed; #include using std::setprecision; // initialize static data member double SavingsAccount::annualInterestRate = 0.0; // calculate monthly interest on account void SavingsAccount::calculateMonthlyInterest() { savingsBalance += savingsBalance * ( annualInterestRate / 12.0 ); } // end function calculateMonthlyInterest // change value of annual interest rate void SavingsAccount::modifyInterestRate( double i ) { annualInterestRate = ( i >= 0 && i <= 1.0 ) ? i : 0.03; } // end function modifyInterestRate // print savings balance void SavingsAccount::printBalance() const { cout << fixed << '$' << setprecision( 2 ) << savingsBalance; } // end function printBalance /************************************************************************** * (C) Copyright 1992-2003 by Deitel & Associates, Inc. and Prentice * * Hall. All Rights Reserved. * * * * DISCLAIMER: The authors and publisher of this book have used their * * best efforts in preparing the book. These efforts include the * * development, research, and testing of the theories and programs * * to determine their effectiveness. The authors and publisher make * * no warranty of any kind, expressed or implied, with regard to these * * programs or to the documentation contained in these books. The authors * * and publisher shall not be liable in any event for incidental or * * consequential damages in connection with, or arising out of, the * * furnishing, performance, or use of these programs. * *************************************************************************/