Chapter 1, Problem 12R

Explanation of Solution

Program code:

main.cpp

//include the requird header files

#include <vector>

#include "CreditCard.h"

//use the namespace

using namespace std;

//define the function textCard()

void testCard()

{

    // vector of CC pointers

    vector <CreditCard*> wallet(10);

    //create the credit card details

    wallet[0] = new CreditCard(5391037593875309,"JoBlo",2500);

    wallet[1] = new CreditCard(3485039933951954,"JoBlo",3500);

    wallet[2] = new CreditCard(6011490232942994,"JoBlo",5000);

    //iterate a for loop

    for (int j = 1; j <= 16; j++)

    {

        // explicit cast

        wallet[0] -> chargeIt(double(j));

        // implicit cast

        wallet[1] -> chargeIt(2 * j);

        wallet[2] -> chargeIt(double(3 * j));

    }

    //iterate a for loop

    for (int i = 0; i < 3; i++)

    {

        //print the card details

           cout << *wallet[i];

        //iterate a while loop to get the balance

        while (wallet[i]->getBalance() > 100.0)

        {

            //call the method makePayment

            wallet[i]->makePayment(100.0);

            //print the new balance

            cout << "New balance = " <<

            wallet[i]->getBalance() << "\n";

        }

        //deleting a walllet

        delete wallet[i];

    }

}

//define the main() method

int main()

{

    //First test case

    CreditCard CC = CreditCard(1234, "Bill gates", 2500);

    CC.chargeIt(1000);

    CC.chargeIt(-100);

    CC.chargeIt(500);

    CC.makePayment(-100);

    CC.makePayment(300);

    cout << CC << endl << endl;

    //given test case

    testCard();

    return EXIT_SUCCESS;

}

Explanation:

In the code,

• Include the required header files.
• Use the namespace.
• Define the “testCard()” method.
  • Create vector pointers
  • Create array “wallet[]” to store credit card details.
  • Iterate a “for” loop.
    • Explicit cast.
    • Implicit cast.
  • Iterate a “for” loop.
    • Print the card details.
    • Iterate a “while” loop to get the balance.
      • Call the method “makepayment()”.
      • Print the new balance.
        • Delete a wallet.
• Define the “main()” function.
  • Enter the credit card details.
  • Call the function “chargeIt()” and “makePayment()” using “CC”.
  • Call the function “testCard()”.
  • Return “EXIT_SUCCESS”.

CreditCard.cpp

//Code for CreditCard.cpp

#include "CreditCard.h"

using namespace std;

//define the constructor CreditCard

CreditCard::CreditCard(long long int no, const string& nm, int lim, double bal)

{

    //declare the required variables

    number = no;

    name = nm;

    limit = lim;

    balance = bal;

}

//define a function chargeIt()

bool CreditCard::chargeIt(double price)

{

    if(price <= 0)

    {

        //print error message when price is negative

        cout << "Error: Input argument must be positive.\n";

        //return false

        return false;

    }

    //if the condition is true

    if (price + balance > double(limit))

    {

        //return false

        return false;

    }

    //add price to balance

    balance += price;

    //update fraction

    fraction = double(balance)*100.0/limit;

    //if the condition is true

    if(fraction > FRACTION_LIMIT)

    {

//print warning message when fraction is more than 50%

printf("Warning: the current balance on credit card %lld is %.2f%c of your limit.\n", number, fraction, '%');

    }

    // the charge goes through

    return true;

}

//define the function makePayment

void CreditCard::makePayment(double amount)

{

    //if amount less than or equal to 0

    if(amount <= 0)

    {

        //print error message when amount is negative

        cout << "Error: Input argument must be positive...