DESPERATE

[trobbers405]

How would I declare the print functions for this mess?
Sorry for the length, professor is weird and likes one file

#include <iostream>
using std::cout;
using std::endl;
using std::ios;

#include <iomanip>
using std::setprecision;

#include <fstream>
using std::ifstream;

#include <cstring>
#include <cstdlib>

class Square
{
public:
	Square(char*);
	void print(Square*);
	void setSquare(Square*, double);
private:
	double side;
};

Square::Square(char* token)
{
	if (atof(token) == 0)
		side = 0;
	else
		side = atof(token);
}

class Rectangle
{
public:
	Rectangle(char*, char*);
	void print(Rectangle*);
	void setRectangle(Rectangle*, double, double);
private:
	double length;
	double width;
};

Rectangle::Rectangle(char* tokena, char* tokenb)
{
	if (atof(tokena) == 0)
		length = 0;
	else
		length = atof(tokena);
	if (atof(tokenb) == 0)
		width = 0;
	else
		width = atof(tokenb);
}

class Circle
{
public:
	Circle(char*);
	void print(Circle*);
	void setCircle(Circle*, double);
private:
	double radius;
};

Circle::Circle(char* token)
{
	if (atof(token) == 0)
		radius = 0;
	else
		radius = atof(token);
}

class Cylinder
{
public:
	Cylinder(char*, char*);
	void print(Cylinder*);
	void setCylinder(Cylinder*, double, double);
private:
	double radius;
	double height;
};

Cylinder::Cylinder(char* tokena, char* tokenb)
{
	if (atof(tokena) == 0)
		radius = 0;
	else
		radius = atof(tokena);
	if (atof(tokenb) == 0)
		height = 0;
	else
		height = atof(tokenb);
}

class Cube
{
public:
	Cube(char*);
	void print(Cube*);
	void setCube(Cube*, double);
private:
	double side;
};

Cube::Cube(char* token)
{
	if (atof(token) == 0)
		side = 0;
	else
		side = atof(token);
}

class Prism
{
public:
	Prism(char*, char*, char*);
	void print(Prism*);
	void setPrism(Prism*, double, double, double);
private:
	double length;
	double width;
	double height;
};

Prism::Prism(char* tokena, char* tokenb, char* tokenc)
{
	if (atof(tokena) == 0)
		length = 0;
	else
		length = atof(tokena);
	if (atof(tokenb) == 0)
		width = 0;
	else
		width = atof(tokenb);
	if (atof(tokenc) == 0)
		height = 0;
	else
		height = atof(tokenc);
}

const int MAX_CHARS_PER_LINE = 512;
const int MAX_TOKENS_PER_LINE = 20;
const char* DELIMITER = " ";
const double PI = 3.14159265358979323846;

void Square::print(Square* sq)
{
	cout << "SQUARE" << " side=";
	cout.unsetf(ios::fixed|ios::showpoint);
	cout << setprecision(6);
	cout << sq->side << " area=";
	cout.setf(ios::fixed|ios::showpoint);
	cout << setprecision(2);
	cout << (sq->side * sq->side) << " perimeter=" << (4*sq->side) << endl;
}

void Rectangle::print(Rectangle* re)
{
	cout << "RECTANGLE" << " length=";
	cout.unsetf(ios::fixed|ios::showpoint);
	cout << setprecision(6);
	cout << re->length << " width=" << re->width << " area=";
	cout.setf(ios::fixed|ios::showpoint);
	cout << setprecision(2);
	cout << (re->length * re->width) << " perimeter=" << ((2*re->length)+(2*re->width)) << endl;
}

void Circle::print(Circle* ci)
{
	cout << "CIRCLE" << " radius=";
	cout.unsetf(ios::fixed|ios::showpoint);
	cout << setprecision(6);
	cout << ci->radius << " area=";
	cout.setf(ios::fixed|ios::showpoint);
	cout << setprecision(2);
	cout << (PI*(ci->radius * ci->radius)) << " circumference=" << (2*PI*ci->radius) << endl;
}

void Cube::print(Cube* cu)
{
	cout << "CUBE" << " side=";
	cout.unsetf(ios::fixed|ios::showpoint);
	cout << setprecision(6);
	cout << cu->side << " surface area=";
	cout.setf(ios::fixed|ios::showpoint);
	cout << setprecision(2);
	cout << ((cu->side*cu->side)*6) << " volume=" << (cu->side*cu->side*cu->side) << endl;
}

void Prism::print(Prism* pr)
{
	cout << "PRISM" << " length=";
	cout.unsetf(ios::fixed|ios::showpoint);
	cout << setprecision(6);
	cout << pr->length << " width=" << pr->width << " height=" << pr->height << " surface area=";
	cout.setf(ios::fixed|ios::showpoint);
	cout << setprecision(2);
	cout << ((2*pr->length*pr->width)+(2*pr->width*pr->height)+(2*pr->length*pr->height));
	cout << " volume=" << (pr->length*pr->width*pr->height) << endl;
}

void Cylinder::print(Cylinder* cy)
{
	cout << "CYLINDER" << " radius=";
	cout.unsetf(ios::fixed|ios::showpoint);
	cout << setprecision(6);
	cout << cy->radius << " height=" << cy->height << " surface area=";
	cout.setf(ios::fixed|ios::showpoint);
	cout << setprecision(2);
	cout << ((2*PI*(cy->radius*cy->radius)) + (2*PI*cy->radius*cy->height));
	cout << " volume=" << (PI*(cy->radius*cy->radius)*cy->height) << endl;
}
void Square::setSquare(Square* sq, double tempa)
{
	sq->side = tempa;
}

void Rectangle::setRectangle(Rectangle* re, double tempa, double tempb)
{
	re->length = tempa;
	re->width = tempb;
}

void Circle::setCircle(Circle* ci, double tempa)
{
	ci->radius = tempa;
}

void Cylinder::setCylinder(Cylinder* cy, double tempa, double tempb)
{
	cy->radius = tempa;
	cy->height = tempb;
}

void Cube::setCube(Cube* cu, double tempa)
{
	cu->side = tempa;
}

void Prism::setPrism(Prism* pr, double tempa, double tempb, double tempc)
{
	pr->length = tempa;
	pr->width = tempb;
	pr->height = tempc;
}

int main()
{
	ifstream fin;
	int x = 0;
	void* shapes[100] = {};
	int id[100] = {}; // 0=square, 1=rectangle, 2=circle, 3=cube, 4=prism, 5=cylinder
	fin.open("geo.txt");
	if (!fin.good())
		return 1;
	while (!fin.eof())
	{
		char buff[MAX_CHARS_PER_LINE];
		fin.getline(buff, MAX_CHARS_PER_LINE);
		int n = 0;
		char* token[MAX_TOKENS_PER_LINE] = {0};
		token[0] = strtok(buff, DELIMITER);
		if (token[0])
		{
			for (n = 1; n < MAX_TOKENS_PER_LINE; n++)
			{
				token[n] = strtok(0, DELIMITER);
				if (!token[n]) break;
			}
		}
		for (int i = 0; i < n; i++)
		{
			if (!((strcmp(token[0],"SQUARE") == 0) || (strcmp(token[0],"RECTANGLE") == 0) || (strcmp(token[0],"CUBE") == 0) || (strcmp(token[0],"CIRCLE") == 0) || (strcmp(token[0],"PRISM") == 0) || (strcmp(token[0],"CYLINDER") == 0)))
			{
				cout << token[0] << " invalid object" << endl;
				i=n;
			}
			if(strcmp(token[0],"SQUARE") == 0)
			{
				if (n == 1)
				{
					token[1] = "0";
				}
				Square* sq = new Square(token[1]);
				shapes[x] = sq;
				id[x] = 0;
				i=n;
				x++;
			}
			if(strcmp(token[0],"RECTANGLE") == 0)
			{
				if (n == 1)
				{
					token[1] = "0";
					token[2] = "0";
				}
				if (n == 2)
				{
					token[2] = "0";
				}
				Rectangle* re = new Rectangle(token[1], token[2]);
				shapes[x] = re;
				id[x] = 1;
				i=n;
				x++;
			}
			if(strcmp(token[0],"CIRCLE") == 0)
			{
				if (n == 1)
				{
					token[1] = "0";
				}
				Circle* ci = new Circle(token[1]);
				shapes[x] = ci;
				id[x] = 2;
				i=n;
				x++;
			}
			if(strcmp(token[0],"CUBE") == 0)
			{
				if (n == 1)
				{
					token[1] = "0";
				}
				Cube* cu = new Cube(token[1]);
				shapes[x] = cu;
				id[x] = 3;
				i=n;
				x++;
			}
			if(strcmp(token[0],"PRISM") == 0)
			{if (n == 1)
				{
					token[1] = "0";
					token[2] = "0";
					token[3] = "0";
				}
				if (n == 2)
				{
					token[2] = "0";
					token[3] = "0";
				}
				if (n == 3)
				{
					token[3] = "0";
				}
				Prism* pr = new Prism(token[1], token[2], token[3]);
				shapes[x] = pr;
				id[x] = 4;
				i=n;
				x++;
			}
			if(strcmp(token[0],"CYLINDER") == 0)
			{
				if (n == 1)
				{
					token[1] = "0";
					token[2] = "0";
				}
				if (n == 2)
				{
					token[2] = "0";
				}
				Cylinder* cy = new Cylinder(token[1], token[2]);
				shapes[x] = cy;
				id[x] = 5;
				i=n;
				x++;
			}
		}	
	}
	fin.close();
	for (int c = 0; c < x; c++)
	{	
		//Print Functions Go Here
	}
	for (int d = 0; d < x; d++)
	{
		if (id[d] == 0)
			delete (Square*)shapes[d];
		if (id[d] == 1)
			delete (Rectangle*)shapes[d];
		if (id[d] == 2)
			delete (Circle*)shapes[d];
		if (id[d] == 3)
			delete (Cube*)shapes[d];
		if (id[d] == 4)
			delete (Prism*)shapes[d];
		if (id[d] == 5)
			delete (Cylinder*)shapes[d];
	}
	return 0;
}

[FlashDrive]

Hello? Did you not read the rules? This forum is NOT for HOMEWORK! You can ask questions or ask for help in some certain things but you are NOT allowed to ask for a working HOMEWORK.

[trobbers405]

i am sorry, i have been sick the past week and am kinda stuck and not thinking straight

[FlashDrive]

What's exactly your prob? Don't you know how to use these print(whatever)-functions in line 377?

[trobbers405]

this is what was there before we changed the classes from structs

for (int c = 0; c < x; c++)
	{
		if (id[c] == 0)
			printSquare((square*)shapes[c]);
		if (id[c] == 1)
			printRectangle((rectangle*)shapes[c]);
		if (id[c] == 2)
			printCircle((circle*)shapes[c]);
		if (id[c] == 3)
			printCube((cube*)shapes[c]);
		if (id[c] == 4)
			printPrism((prism*)shapes[c]);
		if (id[c] == 5)
			printCylinder((cylinder*)shapes[c]);
	}

but now with classes and the public and private tags i am a little lost and this professor is the only comp sci teacher that doesn't post his lectures online

[FlashDrive]

these

[...]public and private tags[...]

, how you name them, are for the access. You can't use as private declared functions or variables outside the class. The opposite of this is public. E.g. in your class Rectangle (l. 33-42) you can access the constructor (Rectangle(/*whatever*/)) from outside the class, but you can't do so with length or width.
I think that you don't have to change anything, because in a

struct

you only have public variables but in a class is everything which is not specified as public or private automatically protected. I guess that protected variables can be used from outside the class, but they're like static ones: You can't alter them.

[trobbers405]

i have actually tried that and he doesn't want us to use static and he does want public and private tags.

[FlashDrive]

it is not static, it's protected. But if he doesn't want you to use protected variables, you have to make public functions to return the variable value. E.g.
double get_width() {return width;};
You might use this in Rectangle to get the width of this rectangle.

[FlashDrive]

btt: print() is a class function, isn't it? So you have to make for example

if(id[c]==1)
{
    Rectangle *r=(rectangle *)shapes[c];
    r->print(r);
}

[Bench82]

The main syntactic differences between standalone functions and functions in a class are the calling convention, and the way you access data in the object.

e.g. in the world of pure procedural code, you'd do something like this

struct foo
{
    int n;
};

void func( foo& bar )
{
    bar.n = 5;
} 

and to call the function, you'd do this

int main()
{
    foo bar;
    func( bar );
} 

In the world of object-based programming, the above code would look a bit different

class foo
{
    int n;
public:
    void func()
    {
        n = 5;
    }
}; 

and to call the function, you'd do this

int main()
{
    foo bar;
    bar.func();
} 

Notice that 'func()' no longer accepts a 'foo' argument - because it doesn't need one; it always operates on its current object (As in, whatever is on the left-hand-side of the . or ->). The code is functionally identical, but the organisation of the program is completely different.


If this is your first foray into the world of object-based programming, then I'd strongly suggest looking in your book (or on google) for some basic information about classes.

[ne555]

FlashDrive wrote:

I think that you don't have to change anything, because in a struct
you only have public variables but in a class is everything which is not specified as public or private automatically protected. I guess that protected variables can be used from outside the class, but they're like static ones: You can't alter them.

You can declare members and methods as public private protected in a struct too.
The default visibillity for a struct is public
for a class is private

protected is using with inheritance in order to give the children access, while keep them secure from outsiders

class foo{
//private by default
  int a;
private:
  int b;
protected:
  int c;
public:
  int d;
};

class bar: public foo{
public:
  void method(){
    a = 42; //error foo::a is private
    b = 42; //error foo::b is private
    c = 42; //fine
    d = 42; //fine
  }
};

int main(){
  bar zzz;
  zzz.c = 42; //error foo::c is protected
}

@OP: void Square::print(Square* sq) That make no sense.
As pointed by Bench82 methods operates on its object.
So the prototype should be void Square::print() const (const because the object will not be modified)
The same goes for your settters.


About your code, yuck at your heterogeneous container. Take a look at polymorphism
(or at least abstract it a little)