Here is the link for my program, I want to access the average value which is located in grade.c (calculate_grade) class through driver.c (main function) but I don't know how to make "average" visible
I am working on a physics engine, following the cyclone physics engine source code but a I am having trouble with an error that is occurring in my overloaded operator== function. It is saying that the information is unaccessible.
I am modifying a set of static variables inside of the class's member function. The static variables are private. An example of what I'm doing is as below,
utilities.h ----------- class utilities { private: static int num_nodes;
public: void parse_details(char* );
[Code] ....
I get a compilation error in the function void utilities::parse_details(char* filename)
which says: undefined reference to `utilities::num_nodes'
I've been attempting to create a game with curses and I keep running into the problem of scope. I want to change or use variables of a different class in a different header file. But I don't know if I should use pointers, references or neither. Should I be programming in a manner that doesn't make it necessary to use variables outside of their class?
I am working on a video game that is based on a tutorial I found online and I ran into an issue associated with accessing an object's method inside another class object's function without making the object global which seems bad.
Here is basically how the tutorial set things up in the game: The game has a base class called GameObject then there are other child classes that inherit from this class. The GameObject class has all the basic information an object would have that needs rendered on the screen (x/y position, size of bitmap, bitmap, whether or not it is collidable, etc).
One of the child classes SpaceShip, which is the player so it has attributes and methods associated with managing # of lives and points scored.
There are other child classes of GameObjects in the game that need to take life and add points from the SpaceShip object if they collide with the spaceship or other objects.
In the collision handling routine I basically call a function "void Collided(int objectID)" when a game object collides with another. Within the Collided() routine, there is logic that executes code or other functions based on the objectID it collided with. Some of the collisions require taking life from the spaceship or adding points. The way this was accomplished in the tutorial was with function pointers (see Bullet class constructor and collided method for example). Is this really the best way to handle this sort of thing? It seems like there has to be a simpler way than to keep referencing function pointers in any new class I want to add to the game. I realized this when I went to add a method for the spaceship to fire bullets rather than inside my game class.
We are coding a Blackjack/21 game. I have a Deck.cpp class, Deck.h, Play.cpp (holds Main), and Card.h (holds card struct). I also have a Hand class/header, but I'm not using it yet. This is what is required per instructor.I am having issues accessing the functions that are in my Deck class. I have tried a few other means to access the class's function, but I've already gotten rid of those. These three are my latest attempts with the specific errors in the comment on the line the error was happening. ve.
Here is my Deck.h
#pragma once #include <iostream> #include <fstream> #include <string> #include <cstdlib> #include <ctime> #include <iomanip> #include "Card.h" #include "Hand.h" using namespace std; class Deck
I have two classes, a Package class and a Person class. The Package class has two Person objects has member variables, a Sender and a Receiver. While overloading the << operator for the Package class so that it will make an output label from everything in the Package class. Here is my code...
class Package{ public: Person Sender; Person Reciever; int weight; double cost; friend ostream &operator<<(ostream &out, Package &pack);
[Code] .....
So my problem is on that last output line, I am unable to call Sender.getName()... etc. Is there a proper syntax so that I can access the members of the Person class while overloading the << operator for the Package class?
I have an example where I have a variable belonging to a base class, but I would like to tell the compiler that it actually belongs to a derived class. How can I do this?
// base class: R0 // derived class: R1 // see function SetR1 for the problem class R0 { public: int a;
#include<iostream> #include<conio.h> #include<string> using namespace std; class ir; class Bank_acc { private: string name,type,s; long int accno,temp,balance,in;
[Code]....
errors are:
|6|error: forward declaration of 'class ir'| |54|error: invalid use of incomplete type 'class ir'| |99|error: no matching function for call to 'ir::interest()'|
I have defined a class in a header file; just the class, no templates involved. I have a program where I'm reading in data in string format. Each string consists of a word, a delimiter, and a variable name. Example:
cajun/mustard
I want to take that string and make it the variable name of that class type. It would be implemented along the lines of:
Code: string str; //read/process string here, get: str = "mustard"; createName(str); //pass string to creator function When the function is called, I should get the variable: Class mustard;
Thing is, I'm not supposed to know beforehand what the variable names are, only that I create them as they are read in. It could be mustard, it could be Maynard_James_Keenan, it could even be bazinga.
My problem is, what do I do for createName()? I've looked into the concepts of pairing, Factory implementation, and maps, but I don't think they answer my question.
(P.S. if I run into the same variable name being read in twice, what steps can I take to make sure that a duplicate variable isn't created? Do I need to add in code, or does the compiler know to watch for multiple variables of the same name?)
I want to make a destructor counter...So it needs to be outside that specific instance of the class. And i want to keep it hidden. I don't want to be able to access it from outside the class...I Don't want main.cpp to have access to this variable
My program works before i declare a new variable in class. Right after i declared a new int variable called prevans in my guess class, my program crashes when it runs.
I don't understand why my compiler gives me this error when I'm trying to run this code:
Code:
#include <iostream> #include <cmath> using namespace std; class Airplane { public: Airplane(); ~Airplane();
[Code]...
The variable is protected. Yeah, that's right. But shouldn't a derived class be able to reach it? Or is it only in a function that the derived class is able to reach protected variables and isn't able to reach protected variables in the constructor?
I am creating a SpaceShip class, which has arrays for weapon names and damage, and variables for shields power, hull, engine power, and mass. I created two instances of the 'SpaceShip' class, 'ScoutShip', and 'Cruser'. When one of them calls the 'FireWeapons' function, it has the other call the 'TakeDamage' function, but for some reason the 'sheildPower' resets after 'TakeDamage' ends.
#include <iostream> #include <vector> using namespace std; class SpaceShip {
I am trying to add data from a file that would go into a class that would later go into a vector of a class. I'm not really sure how to do it exactly. Here is the code:
Champion_Info.h
#ifndef CHAMPION_INFO_H_INCLUDED #define CHAMPION_INFO_H_INCLUDED #include <vector> #include <string> using namespace std; class Champ_Info {