//DISPLAY 5.9 Supermarket Pricing
//Determines the retail price of an item according to
//the pricing policies of the Quick-Shop supermarket chain.
#include <iostream>

const double LOW_MARKUP = 0.05; //5%
const double HIGH_MARKUP = 0.10; //10%
const int THRESHOLD = 7; //Use HIGH_MARKUP if not expected
                         //to sell in 7 days or less.

void introduction( );
//Postcondition: Description of program is written on the screen.

void getInput(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 giveOutput(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 wholesaleCost, retailPrice;
    int shelfTime;
    introduction( );
    getInput(wholesaleCost, shelfTime);
    retailPrice = price(wholesaleCost, shelfTime);
    giveOutput(wholesaleCost, shelfTime, retailPrice);
    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 getInput(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 giveOutput(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;
}

//Uses defined constants LOW_MARKUP, HIGH_MARKUP, and THRESHOLD:
double price(double cost, int turnover)
{
    if (turnover <= THRESHOLD)
        return ( cost + (LOW_MARKUP * cost) );
    else
        return ( cost + (HIGH_MARKUP * cost) );
}