C++ Function overloading, templates

 C++, Programming  No Responses »
Mar 182011
 

Function overloading and using templates are extremely useful when trying to not write duplicate methods with the same parameters, but only different types.

//main.cpp
#include <iostream>

using namespace std;

void get2Values  (int &data1, int &data2);
void get2Values  (double &data1, double &data2);

void print2Values  (const int &data1,const int &data2);
void print2Values (const double &data1,const double &data2);

template <class dataType>
void  swapC (dataType &a,  dataType &b);

int main ()
{
   int first, second;
   double dFirst, dSecond;

    get2Values(first, second);
    get2Values(dFirst, dSecond);

    print2Values(first, second);
    print2Values(dFirst, dSecond);

    cout << endl << "--Swap--" ;

    swapC<int>(first, second);
    swapC<double>(dFirst, dSecond);

    print2Values(first, second);
    print2Values(dFirst, dSecond);

	cout << endl;
	cin.get();
	return 0;
}

void  get2Values (double &data1, double &data2)
{
	cout << "Enter Double 1 ---> ";
	cin >> data1;
	cout << "Enter Double 2 ---> ";
	cin >> data2;
}

void  get2Values (int &data1, int &data2)
{
	cout << "Enter int 1 ---> ";
	cin >> data1;
	cout << "Enter int 2 ---> ";
	cin >> data2;
}

void  print2Values (const double &data1,const double &data2)
{
	cout << endl << "Double 1 ---> " << data1;
	cout << endl << "Double 2 ---> " << data2;
}
void  print2Values (const int &data1,const int &data2)
{
	cout << endl << "Int 1 ---> " << data1;
	cout << endl << "Int 2 ---> " << data2;
}

template <class dataType>
void  swapC (dataType &a,  dataType &b)
{
	dataType temp = a;  a = b;  b = temp;
}

The output should be:

Enter int 1 ---> 1
Enter int 2 ---> 2
Enter Double 1 ---> 3.21
Enter Double 2 ---> 8.125647

Int 1 ---> 1
Int 2 ---> 2
Double 1 ---> 3.21
Double 2 ---> 8.12565
--Swap--
Int 1 ---> 2
Int 2 ---> 1
Double 1 ---> 8.12565
Double 2 ---> 3.21

The template function allows you to pass in any value, saving you from creating the two methods above unique to double and int.

C++ Basic Asking for Input ($$$)

 C++, Programming  No Responses »
Mar 162011
 

I admit this is a terrible example I wrote up a few months ago. You should obviously have a temp variable so you aren’t casting all the time. But the point of the lab was to test user input, in which it performs just fine and is clean.

//main.cpp
#include <iostream>

using namespace std;

int main ()
{
	double purchaseAmount, cashPaid, temp;
	int change;

	cout << "Enter the purchase price: ";
	cin >> purchaseAmount;
	cout << "Enter the cash tendered: ";
	cin >> cashPaid;

	temp = cashPaid - purchaseAmount;
	change = int (temp * 100);

	cout << "Your change: " << change << " cents" << endl;
	int numQuarters = int(change/25);
	cout << "Quarters: " << numQuarters << endl;
	int numDimes  = int((change-numQuarters*25)/10);
	cout << "Dimes: " << numDimes << endl;
	int numNickels = int((change-numQuarters*25-numDimes*10)/5);
	cout << "Nickels: " << numNickels << endl;
	int numPennies = int((change-numQuarters*25-numDimes*10-numNickels*5)/1);
	cout << "Pennies: " << numPennies << endl;

	cin.get();
	return 0;
}

The output should be:

Enter the purchase price: 10.25  //10.25 was inputted
Enter the cash tendered: 20.21  //20.21 was inputted
Your change: 996 cents
Quarters: 39
Dimes: 2
Nickels: 0
Pennies: 1

And yes, I have noticed the divide by one. Its left in there to keep the standard so its easier to see the pattern of calculating the individual change.

C++ Data Types, Sizes, Values, and Basic Operators

 C++  No Responses »
Mar 152011
 

Data Types and Sizes

Just a basic look into a few different (basic) data types that C++ operators. Compared to Actionscript, ints are the same (non-decimal numbers). Unsinged integers (or uints in AS3) have the same positive, non-decimal values. Floats, doubles, long doubles are like Numbers in AS3, holding decimal values at increasing precision. Chars aren’t available in AS3, but are the same as single length strings.

//main.cpp

#include <iostream>

using namespace std;

int main ()
{
	int myInt = 1;
	long myLong = 2;
	unsigned int myUnsignedInt = 3;
	char myChar = 'D';
	float myFloat = 5.0;
	double myDouble = 6.00;
	long double myLongDouble = 7.0000000000;
	bool myBool = false;
	int myCharASCII = int(myChar);
	int myRandomInt = 98;

	cout < < "The value of myInt = " << myInt << "          The byte size of myInt is " << sizeof (myInt) << " bytes." << endl;
	cout << "The value of myLong = " << myLong << "         The byte size of myLong is " << sizeof (myLong) << " bytes." << endl;
	cout << "The value of myUnsignedInt = " << myUnsignedInt << "  The byte size of myUnsignedInt is " << sizeof (myUnsignedInt) << " bytes." << endl;
	cout << "The value of myChar = " << myChar << "         The byte size of myChar is " << sizeof (myChar) << " bytes." << endl;
	cout << "The value of myFloat = " << myFloat << "        The byte size of myFloat is " << sizeof (myFloat) << " bytes." << endl;
	cout << "The value of myDouble = " << myDouble << "       The byte size of myDouble is " << sizeof (myDouble) << " bytes." << endl;
	cout << "The value of myLongDouble = " << myLongDouble << "   The byte size of myLongDouble is " << sizeof (myLongDouble) << " bytes." << endl;
	cout << "The value of myBool = " << myBool << "         The byte size of myBool is " << sizeof (myBool) << " bytes." << endl<< endl;
	cout << "Letter = " << myChar << "                  The ASCII position = " << myCharASCII << endl;
	cout << "The ASCII position = " << myRandomInt << "     Letter = " << char(myRandomInt) << endl << endl;

	cin.get();
	return 0;
}

The output should be:
Continue reading »

C++ Starting Basic Source Code Examples Series(?)

 C++  No Responses »
Mar 142011
 

I’m not a pro. I’m not experienced with this, besides half a year of working with the language. I’d love some comments and improvements on any and all code I put online. I currently work with the really old Bloodshed Software’s Dev-C++ (Version 4.9.8.0) with its Mingw compiler.

I’ll assume that you’ve already gotten the program set up and have a blank project open. 

//main.cpp

#include <iostream>

using namespace std;

int main ()
{
	cout << "Name - Mr. Cake" << endl;
	cout << "Grade in School - 9000th" << endl << endl;
	cout << "Period      Course" << endl << endl;
	cout << "     1      Math" << endl;
	cout << "     2      Computer Science" << endl;
	cout << "     3      Science" << endl;
	cout << "     4      History" << endl;
	cout << "     5      Language Arts" << endl;
	cout << "     6      Sports" << endl << endl;
	cout << "Computer at home - Windows 7" << endl;

	cin.get();
	return 0;
}

The output should be:

Name - Mr. Cake
Grade in School - 9000th

Period      Course

     1      Math
     2      Computer Science
     3      Science
     4      History
     5      Language Arts
     6      Sports

Computer at home - Windows 7