C++ Reference

////////////////////////////////////////////////////////////////////////////

on class manageFunctionPointer.cpp

////////////////////////////////////////////////////////////////////////////

//declare a function pointer

void (*pfLoad) (void) = 0;

//assign function pointer

pfLoad = loadLevel;

////////////////////////////////////////////////////////////////////////////

on class main.cpp

////////////////////////////////////////////////////////////////////////////

//call from manageFunctionPointer.cpp

extern void (*pfLoad) (void) ;

//call function pointer

eg. 1234567

// return first 3 digits

unsigned HashFirst3(unsigned no)

{

     return no /  10000;

}

// return last 3 digits

unsigned HashFirst3(unsigned no)

{

     return no % 10000;

}

1) dont need to #include "your other file"

2) provide function prototype in main.c

3) implement function in anotherFile.c

#include <iostream>

//Euclid's algorithm int main() { //store 2 numbers int num1, num2;

std::cout<<"enter 1st value"<<std::endl; std::cin>> num1;

std::cout<<"enter 2nd value"<<std::endl; std::cin>> num2;

//check for smaller & bigger value int smallValue, bigValue;

if(num2 > num1) { smallValue = num1; bigValue = num2; } else { smallValue = num2; bigValue = num1; }

//do Euclid's algorithm

//get the reminder unsigned int reminder = bigValue % smallValue;

//check if reminder is 0, if not keep dividing while(reminder!=0) { bigValue = smallValue; smallValue = reminder;

reminder = bigValue % smallValue; }

//GCD is found std::cout<<"GCD is " << smallValue <<std::endl;

Keyword (reserved for compiler)

char , int, sizeof, while .... anything that turn blue in your Visual Studio.

Identifiers (Use to name things)

_myFunction()    //OK!

MyFunction()      // OK!

int 1myVariable  // NO!

int myVariable$  // NO!

Constants (assignment with value)

int i = 1;

float f = 10.4F;

double d = 10.12;

For C standard

int main(void)

int main(int argc, char * argv[]) [this parameter allow you to access environment variable, nothing complicated :) ]

why?

int main() in C means taking unknown number of argument, not no argument at all.

void main() is BAD.

void main() is BAD.

void main() is BAD.

why?

just not good for assembly language stomach :(

*****

For C++ standard

int main()

header file

function prototypes

global variable

main program()

{

   local variable

   statements

class Bulk_item : public Item_base 

    Point Point::operator+(const Point &rhs) const

    {

        Point point;

        point.x_ = x_ + rhs.x_;

        point.y_ = y_ + rhs.y_;

        return point;

    }

    Point Point::operator+(double a) const

    {

        Point point;

        point.x_ = x_ + a;

        point.y_ = y_ + a;

        //std::cout<< "returning x "<<  point.x_<<"," << point.y_ <<std::endl;

        return point;

    }

    Point Point::operator-(double a) const

    {

        Point point;

        point.x_ = x_ - a;

        point.y_ = y_ - a;

        return point;

    }

    Point Point::operator*(double a) const

    {

        Point point;

        point.x_ = x_ * a;

        point.y_ = y_ * a;

        return point;

    }

    Point Point::operator%(double a) const

    {

        double b = DegreesToRadians(a);

        double cosA=cos(b);

        double sinA=sin(b);

        Point point;

        point.x_ = (x_* cosA) - (y_*sinA);

        point.y_ = (x_* sinA) + (y_*cosA);

                 if(point.x_ > -EPSILON && point.x_ < EPSILON)

        {

            point.x_ = 0.0;

        }

        if(point.y_ > -EPSILON && point.y_ < EPSILON)

        {

            point.y_ = 0.0;

        }

        return point;

    }

    double Point::operator-(const Point& p)

    {

        double dist;

        double pointX= (p.x_ - x_) * (p.x_ - x_) ;

        double pointY= (p.y_ - y_) * (p.y_ - y_) ;

        dist = pointX + pointY;

        dist = sqrt(dist);

        return dist;

    }

    Point Point:: operator^(const Point& p)

    {

        Point point;

        point.x_ = ((x_+p.x_)/2);

        point.y_ = ((y_+p.y_)/2);

        return point;

    }

    Point& Point::operator+=(const Point& p)

    {

        this->x_ +=p.x_;

        this->y_ +=p.y_;

        return *this;

    }

    Point& Point::operator+=(double a)

    {

        this->x_ +=a;

        this->y_ +=a;

        return *this;

    }

    Point& Point::operator++() //prefix

    {

        ++(this->x_);

        ++(this->y_);

        return *this;

    }

    Point Point::operator++(int)

    {

        Point point;

        point.x_ = x_++;

        point.y_ = y_++;

        return point;

    }

    Point Point::operator-()

    {

        Point p;

        p.x_ = -x_;

        p.y_ = -y_;

        return p;

    }

    std::istream& operator>>(std::istream& is, Point& p)

    {

        is >> p.x_;

        is >> p.y_;

        is.get();

        return is;

    }

    std::ostream& operator<<(std::ostream& os, const Point& p)

    {

        os << "("<<p.x_ <<", "<<p.y_ << ")";

        return os;

Linker ->System->subsystem, change console to windows.

Go to property -> Linker -> Input -> Additional Dependencies

Edit and add this.

opengl32.lib

glu32.lib

odbc32.lib

odbccp32.lib

Pointer = Gimmi the value!

some unicode problem.

eg. (NULL, "text_error" , "text_error", NULL)

change to

eg. (NULL,TEXT("text_error"), TEXT("text_error"),NULL)

OR set the configuration setting.

Project -> Project properties ->

Configuration Properties ->General ->

"unsigned int" means that it can only be a POSITIVE NUMBER!