Thread: programs off the tech school's hard drive

I'm on the school's network hard drive, looking around, out of curiousity for what they use in their C++ class. Visual Basic.NET isn't a challenge for me, so it's discouraging and that is why I'm currently getting bad marks until I make some stuff up/settle down.

Anyhow, I'm going to post a few programs here from the drive, and I want anybody who can find errors, etc. with the programs to post them. I can see a few, but this is more or less a thought of, I'd take the course, as it would be fun for me since I do c & c++ during my free time, but, I think this particular course is a bit dodgy.

loop example:

Code:

#include <iostream.h>
void main(void)
// This program calculates the average
// of five user-entered numbers.
{
  int count;
  float num, total, average;

  total = 0.0;

  for (count = 0; count < 5; count++)
  {
    cout << "Enter a number: ";
    cin >> num;
    total = total + num;
  }

  average = total / count;
  cout << "\nThe average of the data entered is " << average;
}

array example:

Code:

/*		Using an array to BUILD PRICE */

/* Include Files */
#include <iostream.h>

void main()
{
const int ARRAY_NUM	= 2;
int price[ARRAY_NUM] = {0};
float quantity[ARRAY_NUM];
float amount[ARRAY_NUM];
int incr;

//magic formulas for printing decimal points
cout.setf(ios::fixed);
cout.setf(ios::showpoint);
cout.precision(2);


// Display directions
cout << "*********************************************************************";
cout << "\n                    The Great Widget Company";
cout << "\n*******************************************************************";
cout << "\nThis program will ask you for prices and quantity of Widgets";
cout << "\nThen the program will display a table showing quantity, Price,";
cout << "and the amount of your purchases";
cout << "\n*******************************************************************\n\n";

/* Building array */
	for (incr = 0; incr < ARRAY_NUM; ++incr)
	{
		cout << "Enter a price:  ";
		cin >> price[incr];
		if (price[incr] == 9999)
				break;
		else
		{
		cout << "\nEnter the quantity purchased:  \n";
		cin >> quantity[incr];
		amount[incr] = quantity[incr];
		}
	}

// Printing the table headings
cout << "\n-----------------------------------------------------------------------";
cout << "\n                       Purchasing Report";
cout << "\n  Quantity                   Price             Amount";
cout << "\n  --------                   -----             ------\n";
 
// Print the array
	for (incr = 0; incr < ARRAY_NUM; ++incr)
	{
		
		cout <<  "      " << quantity[incr] << "                    " << price[incr];
		cout << "               " << amount[incr] << "\n";
	}
cout << "\n\n Thank you for Using Great Widgets\n";
}

function example:

Code:

/*		This program has two functions: Main and total_cost */

#include <iostream.h>

//function prototype 
void total_cost(int, double);

//Global variable
double subtotal;

void main( void )
{
	double price;
	int number;


	cout << "Enter the number of items purchased: ";
	cin >> number;
	cout << "Enter the price per item $";
	cin >> price;

	// function call
	total_cost(number, price);
	
	//magic formulas for printing decimal points
	cout.setf(ios::fixed);
	cout.setf(ios::showpoint);
	cout.precision(2);
	cout << number << " item at "
		 << "$" << price << " each.\n"
		 << "Final bill, including tax, is $" << subtotal
		 << endl;
}
//function heading
void total_cost(int number_par, double price_par)
{
	const double TAX_RATE = 0.05; //5% SALES TAX
	
	subtotal = price_par * number_par;
	subtotal = subtotal + (subtotal * TAX_RATE);
}

int main( )

> #include <iostream.h>
#include <iostream>
using namepsace std;

Originally posted by Shadow
> #include <iostream.h>
#include <iostream>
using namepsace std;

http://www.cpp-home.com/faq/faq.pl?20

I use this method:

Code:

 
#include <iostream>

using std::cout;
using std::endl;

int main( )
{
   cout << "Hello World!" << endl;
   return 0;
}

It doesn't make much difference in small program, but its handy for larger programs where you will be typing std::cout hundreds of times. For objects not used so much I just put std in front of it, eg.

Code:

std::vector<int> inVector;

One other thing, I put argument identifers in function prototypes. It makes it easier to understand what the function does and why it need those arguments in my opinion