//DISPLAY 5.2 void Functions //Program to convert a Fahrenheit temperature to a Celsius temperature. #include <iostream> void initialize_screen( ); //Separates current output from //the output of the previously run program. double celsius(double fahrenheit); //Converts a Fahrenheit temperature //to a Celsius temperature. void show_results(double f_degrees, double c_degrees); //Displays output. Assumes that c_degrees //Celsius is equivalent to f_degrees Fahrenheit. int main( ) { using namespace std; double f_temperature, c_temperature; initialize_screen( ); cout << "I will convert a Fahrenheit temperature" << " to Celsius.\n" << "Enter a temperature in Fahrenheit: "; cin >> f_temperature; c_temperature = celsius(f_temperature); show_results(f_temperature, c_temperature); return 0; } //Definition uses iostream: void initialize_screen( ) { using namespace std; cout << endl; return; } double celsius(double fahrenheit) { return ((5.0/9.0)*(fahrenheit - 32)); } //Definition uses iostream: void show_results(double f_degrees, double c_degrees) { using namespace std; cout.setf(ios::fixed); cout.setf(ios::showpoint); cout.precision(1); cout << f_degrees << " degrees Fahrenheit is equivalent to\n" << c_degrees << " degrees Celsius.\n"; return; // Optional }
//DISPLAY 5.11 Program with a Stub //Determines the retail price of an item according to //the pricing policies of the Quick-Shop supermarket chain. #include <iostream> void introduction( ); //Postcondition: Description of program is written on the screen. void get_input(double& cost, int& turnover); //Precondition: User is ready to enter values correctly. //Postcondition: The value of cost has been set to the //wholesale cost of one item. The value of turnover has been //set to the expected number of days until the item is sold. double price(double cost, int turnover); //Precondition: cost is the wholesale cost of one item. //turnover is the expected number of days until sale of the item. //Returns the retail price of the item. void give_output(double cost, int turnover, double price); //Precondition: cost is the wholesale cost of one item; turnover is the //expected time until sale of the item; price is the retail price of the item. //Postcondition: The values of cost, turnover, and price have been //written to the screen. int main( ) { double wholesale_cost, retail_price; int shelf_time; introduction( ); get_input(wholesale_cost, shelf_time); retail_price = price(wholesale_cost,shelf_time); give_output(wholesale_cost, shelf_time, retail_price); return 0; } //Uses iostream: void introduction( ) { using namespace std; cout << "This program determines the retail price for\n" << "an item at a Quick-Shop supermarket store.\n"; } //Uses iostream: void get_input(double& cost, int& turnover) { using namespace std; cout << "Enter the wholesale cost of item: $"; cin >> cost; cout << "Enter the expected number of days until sold: "; cin >> turnover; } //Uses iostream: void give_output(double cost, int turnover, double price) { using namespace std; cout.setf(ios::fixed); cout.setf(ios::showpoint); cout.precision(2); cout << "Wholesale cost = $" << cost << endl << "Expected time until sold = " << turnover << " days" << endl << "Retail price= $" << price << endl; } //This is only a stub: double price(double cost, int turnover) { return(9.99); //Not correct, but good enough for some testing. }