Question

the source code I have is what i'm supposed to fix for the assignment at the bottom.

cars.cpp source code:

/* Program Cars.cpp reads records from file and writes
them back to another file with the price member
increased by 10%.
*/
#include <fstream>
#include <iostream>
#include <string>
#include "car.h" // car.h header file is included here

using namespace std;

/* Reads data from a file and using it to populate a Car struct and then
return that Car struct
Pre: File dataIn has been openedand contains valid information in the format:
customer name, car make, price , month, date, year (date separated by
space)
Post: The fields of car are read from file dataIn.
*/
Car GetCar(ifstream& dataIn);
/* Writes the data from a Car struct out to a given file
Pre: File dataOut has been opened and contains valid data
Post: The fields of car are written to file dataOut,
appropriately labeled
*/
void WriteCar(ofstream& dataOut, Car car);
int main() {
Car car;
int carCount = 0; // Intialize car count to 0
ifstream dataIn;
ofstream dataOut;

dataIn.open("cars.dat");
dataOut.open("cars.out");
cout << fixed
<< showpoint; // Set numerical formatting to show decimal points

car = GetCar(dataIn); // Priming read to get first car from file

// Continue reading all data in file
while (dataIn) {
carCount++; // Increment car counter

car.price = car.price * 1.10; // Increase car price by 10%

WriteCar(dataOut, car); // Write out updated car data to output file

car = GetCar(dataIn); // Get next car from file
}
// Display number of cars read from file and written
cout << carCount << " cars processed.\n";

return 0;
}

// ********************************************************

Car GetCar(/*INOUT */ ifstream& dataIN) {
Car car; // Local variable to hold and return car info

// Read all data from file into car variable
// Changed in input to read first name and last name seperately using struct
// personType
dataIN >> car.customer.firstName >> car.customer.lastName >> car.make;
dataIN >> car.price >> car.purchased.day >> car.purchased.month >>
car.purchased.year;

// Return car with data from file
return car;
}

// **********************************************************

void WriteCar(/* INOUT */ ofstream& dataOut, /*IN*/ Car car) {
// Write out all data contained in car to output file
// Changed in output to write first name and last name
dataOut << "Customer: " << car.customer.firstName << " "
<< car.customer.lastName << endl
<< "Make: " << car.make << endl
<< "Price: " << car.price << endl
<< "Purchased: " << car.purchased.day << "/" << car.purchased.month
<< "/" << car.purchased.year << endl;
}

car.h code:

#ifndef CAR /* include guard to ensure that they are not inserted multiple times into a single .cpp file. */
#define CAR

// Structure to hold information about customer
struct personType {
string firstName;
string lastName;
};
// Structure to hold date information
struct Date {
int month;
int day;
int year;
};
// Structure to hold information on a car sold
struct Car {
personType customer;
string make;
float price;
Date purchased;
};

#endif

assignment details:

This one uses the same cars.cpp as a base, but has nothing to do with pointers. (That's why it's a separate exercise.) In this case you're going to modify the program so that rather than just printing data directly to the screen, it will also store the data in an array of type carArray, assuming no more than 50 cars.

Use the definitions:

Car carArray[50];
int carCount = 0;

Modify cars.cpp so that it will store each car read in the next element of the array.

Submit:

• Updated cars.cpp with commented source code

Answer 1

Program code to copy:- (The changes made in cars.cpp is in bold)

//cars.cpp code

/* Program Cars.cpp reads records from file and writes
them back to another file with the price member
increased by 10% using array.
First data read from file will be stored in array and
the content of array is written into output file.
*/
#include <fstream>
#include <iostream>
#include <string>
#include "car.h" // car.h header file is included here

using namespace std;

/* Reads data from a file and using it to populate a Car struct and then
return that Car struct
Pre: File dataIn has been openedand contains valid information in the format:
customer name, car make, price , month, date, year (date separated by
space)
Post: The fields of car are read from file dataIn.
*/
Car GetCar(ifstream& dataIn);
/* Writes the data from a Car struct out to a given file
Pre: File dataOut has been opened and contains valid data
Post: The fields of car are written to file dataOut,
appropriately labeled
*/
void WriteCar(ofstream& dataOut, Car car[], int carCount);
int main() {
   //Definition of array of type Car
   Car car[50];
   int carCount = 0; // Intialize car count to 0
  
   ifstream dataIn;
   ofstream dataOut;

   dataIn.open("cars.dat");
   dataOut.open("cars.out");
   cout << fixed
   << showpoint; // Set numerical formatting to show decimal points

   // Priming read to get first car from file and
   //storing into array
   car[carCount] = GetCar(dataIn);

   // Continue reading all data in file
   //and storing into array of type Car
   while (dataIn) {
       carCount++; // Increment car counter

   //Storing price into array
   car[carCount].price = car[carCount].price * 1.10; // Increase car price by 10%

   // Get next car from file and storing into array
   car[carCount] = GetCar(dataIn); // Get next car from file
}
   // Write out updated car data to output file
   //Function will be called only once as all the data read
   //from file is stored in array.
   //Array and number of car count is passed as a paramenter
   WriteCar(dataOut, car, carCount);
   // Display number of cars read from file and written
   cout << carCount << " cars processed.\n";

   return 0;
}

// ********************************************************

Car GetCar(/*INOUT */ ifstream& dataIN) {
   Car car; // Local variable to hold and return car info

   // Read all data from file into car variable
   // Changed in input to read first name and last name seperately using struct
   // personType
   dataIN >> car.customer.firstName >> car.customer.lastName >> car.make;
   dataIN >> car.price >> car.purchased.day >> car.purchased.month >>
   car.purchased.year;

   // Return car with data from file
   return car;
}

// **********************************************************
//Function receives output file stream, array of type Car and
//car count as parameter
void WriteCar(/* INOUT */ ofstream& dataOut, /*IN*/ Car car[], int carCount) {
   // Write out all data contained in car array to output file
   // Changed in output to write first name and last name
   for(int i=0; i<carCount; i++) {
       dataOut << "Customer: " << car[i].customer.firstName << " "
   << car[i].customer.lastName << endl
   << "Make: " << car[i].make << endl
   << "Price: " << car[i].price << endl
   << "Purchased: " << car[i].purchased.day << "/" << car[i].purchased.month
   << "/" << car[i].purchased.year << endl;
   }  
}

//car.h code

#include <iostream>
using namespace std;
#ifndef CAR /* include guard to ensure that they are not inserted multiple times into a single .cpp file. */
#define CAR

// Structure to hold information about customer
struct personType {
string firstName;
string lastName;
};
// Structure to hold date information
struct Date {
int month;
int day;
int year;
};
// Structure to hold information on a car sold
struct Car {
personType customer;
string make;
float price;
Date purchased;
};

#endif

Screenshot of output:-

Screenshot of content of file names "cars.out" created after the execution of program :-

Before execution of above program code you need to create a input file named "cars.dat" .

Sample of file "cars.dat":-

Ryan Hilliard CHEVROLET 25000 15 10 2014
Kyle Jiwani FORD 31000 17 9 2016
Edward Maun TOYOTA 20000 20 11 2017
Hannah Shrestha VOLKSWAGEN 29000 21 5 2018