I need help with using the infile and outfile operations in C++...

Here's my assignment requirements:

Assignment: Cindy uses the services of a brokerage firm to buy and sell stocks. The firm charges 1.5% service charges on the total amount for each transaction, buy or sell. When Cindy sells stocks, she would like to know if she gained or lost on a particular investment. Write a program that allows Cindy to read input from a file called Stock.txt: 1. The name of the stock.

2. The purchase price of each stock

3. The selling price of each stock

4. The number of stock sold

5. Assumption: Number of stocks bought and sold are equal.

The program writes the following output to a file called StockOutput.txt: 1. The name of the stock

2. The amount invested

3. The amount received after selling the stock.

4. The total service charges

5. Amount gained or lost

Here's the code I've got so far ... the math works but I'm stuck with the in/out files and formatting.

//Header files

#include

#include

#include

using namespace std;

//define constant variables

const double serviceCharge = 0.015;

//Begin main function

int main()

{

//declare variables

string stockName;

int sharesSold;

double sharePurchprice;

double shareSellprice;

double amtInvest;

double amtRet;

double buyService;

double sellService;

double totalService;

double gain_or_loss;

//declare filestream variables

ifstream infile;

ofstream outfile;

//Open the files Stock.txt and stockOutput.txt

infile.open("Stock.txt");

outfile.open("stockOutput.txt");

infile >>stockName >>amtInvest >>amtRet >>totalService >>gain_or_loss;

//Prompt user for name of stock

cout << "Please enter name of stock:";

getline(cin, stockName);

//Prompt for user input of shares sold sharesSold

cout << "Please enter the number of shares sold: ";

//read input from user sharesSold

cin >> sharesSold;

//Prompt for user input of purchase price of shares sharePurchprice

cout << "Please enter the price of share purchase price: ";

//read input from user SharesPurch

cin >> sharePurchprice;

//Prompt for user input of selling price of shares shareSellprice

cout << "Please enter the price of share selling price: ";

//read input from user shareSellprice

cin >> shareSellprice;

//Calculate Service Charge

buyService = serviceCharge * (sharesSold*sharePurchprice);

sellService = serviceCharge * (sharesSold*shareSellprice);

totalService = buyService + sellService;

//Calculate amount invested amtInvest

amtInvest = (sharesSold*sharePurchprice) + buyService;

//Calculate amount invested and total service charge and display to user

cout << "Amount Invested: " << amtInvest << endl;

cout << "Total Service Charge: " << totalService << endl;

//Calculate amount gain and/or lost and display to user

gain_or_loss = (sharesSold*(shareSellprice - sharePurchprice)) - totalService;

//gain or loss if / else loop

if (gain_or_loss > 0)

cout << "Your total gain is : " << gain_or_loss << endl;

else

cout << "You total loss is : " << gain_or_loss << endl;

//Calculate amount after stock sell and display to user

amtRet = (sharesSold*shareSellprice) - sellService;

cout << "Total amount received after sell: " << amtRet << endl;

//end

return 0;

}