C++ :: Initializing Variables In Each Class
Sep 26, 2014
I am working on a homework assignment and have most of the program working, but when I try to compile it keeps telling me to initialize the coin variables in each class. However, they are supposed to be added then removed so I don't want to set them back to zero.
Rewrite the Purse program given in Page 35 with functions to perform insert and remove operations. The function insert (int p, int n, int d, int q) will initialize pennies, nickels, dimes and quarters. The function dollars() will return the dollars. The function remove (int p, int n, int d, int q) will subtract pennies, nickels, dimes and quarters. The function display() returns a new String to print the content of the purse with remaining pennies, nickels, dimes and quarters.
Code:
usingnamespace std;
int insert_money (int *p, int *n, int *d, int *q);
int remove_money (int *p, int *n, int *d, int *q);
int dollars();
int main()
[Code] ....
View 2 Replies
ADVERTISEMENT
Oct 24, 2013
I want to know how to make variables during the program. for example in a program i want to have the player be able to create their own spells or add their own weapons to the game without having to edit the source code. i use sfml 2.0
View 4 Replies
View Related
May 5, 2014
I am trying to initialize this chunk of code without it starting at the main menu in my state program:
boost::asio::io_service io_service;
tcp::resolver resolver(io_service);
tcp::resolver::query query(argv[1], argv[2]);
tcp::resolver::iterator iterator = resolver.resolve(query);
chat_client c(io_service, iterator);
boost::thread t(boost::bind(&boost::asio::io_service::run, &io_service));
char line[chat_message::max_body_length + 1];
This code came from a example at the boost example list: URL.....I want the networking to start when the multiplayer state initializes. This is how my program basically looks like:
//Main.cpp
main() {
if (!quit) {
while( handleing_events ) {
CurrentState->handleEvents();
[code].....
I tried to put the stuff in extern at states.h, and initialize it at Multiplayer(), but in handleEvents & ~Multiplayer, it says "c" is not defined...
View 8 Replies
View Related
Sep 8, 2014
I am new to VC++ 2012. I have this code snippet.
Code:
auto it = query_map.find(U("callback"));
The problem is right under the dot there is a red line the error is
Error1error C2664: 'std::_Tree_iterator<_Mytree> std::_Tree<_Traits>::find(const http::uri::encoded_string &)' : cannot convert parameter 1 from 'const wchar_t [9]' to 'const http::uri::encoded_string &'d:maverickprojectsstrikeforcesrcserverserverserver.cpp26
What is the solution to this error?
View 3 Replies
View Related
Jan 6, 2015
Let's say I have a Car object , and it contains inner Engine object.
Code:
struct Car{
Engine mEngine;
};
In order to initialize the engine object NOT by the default constructor (if it has any) , we use initialization semantics:
Code:
Car::Car:
mEngin(arg1,arg2,...)
{
other stuff here
}
Now it gets tricky: Let's say a Car objects has 10 inner objects, each object has about 5 variables in it . Car is a base class for , e.g. , Toyota class. you don't want the Car class to have a constructor with 50 arguments. Can the inner objects of Car be initialized from the base class , e.g. Toyota?
Code:
class Toyota:
Car(...),
mEngine(...),
mGear(..)
{
...
};
The other options are:
1) like said , create a Car constructor which gets 50 arguments, then initialize Car as whole from Toyota - the code becomes less readable and less intuitive
2) Car constructor which get built-objects as arguments and initialize the inner objects with copy constructor . the code gets more readable but then you create many excess objects .
View 5 Replies
View Related
Mar 7, 2014
I have a class MySeqBuildBlockModule that I am inheriting from: public SeqBuildBlock. Other than constructor and destructor, this class MySeqBuildBlockModule has a method: prep.
class MySeqBuildBlockModule: public SeqBuildBlock {
friend class SeqBuildBlockIRns;
public:
MySeqBuildBlockModule (SBBList* pSBBList0, long TI1_In, long TI2_In)// more arguements in this constructor of derived class
: SeqBuildBlock (pSBBList0)
[code]....
I would have like to intiantiate an object "myIRns_3" of a class defined in third party library
SeqBuildBlockIRns myIRns_3(pSBBList2);
and would like to access it from the prep function as:
double dEnergyAllSBBs_DK = myIRns_3.getEnergyPerRequest();
I tried to instantiate following in either private section or in constructor; but w/o any success:
SeqBuildBlockIRns myIRns_3(pSBBList2);
ERRORS encountered:
When I tried to do it inside the constructor, I get the following errors:
MySBBModule.h(113) : error C2065: 'myIRns_3' : undeclared identifier
MySBBModule.h(113) : error C2228: left of '.getEnergyPerRequest' must have class/struct/union type
MySBBModule.h(116) : error C2065: 'pSBBList' : undeclared identifier
MySBBModule.h(116) : error C2227: left of '->prepSBBAll' must point to class/struct/union
When I tried to do it in private section, I get the following errors:
MySBBModule.h(106) : error C2061: syntax error : identifier 'pSBBList2'
MySBBModule.h(113) : error C2228: left of '.getEnergyPerRequest' must have class/struct/union type
MySBBModule.h(116) : error C2065: 'pSBBList' : undeclared identifier
MySBBModule.h(116) : error C2227: left of '->prepSBBAll' must point to class/struct/union
View 5 Replies
View Related
Feb 4, 2014
I came across a piece of c++ code that seems to be initializing a class object like this:
ImapMailbox *mailbox;
Now the class looks like this:
class ImapMailbox {
public:
ImapMailbox();
ImapMailbox (const QString& mailbox);
~ImapMailbox();
// Methods
void addMessage (ImapMessage *message);
[Code]...
And the constructor looks like this:
ImapMailbox::ImapMailbox()
: d(new ImapMailboxPrivate)
{
d->unseen = d->exists = d->recent = 0;
d->readWrite = false;
d->flags = 0;
}
But this does not seem to be an array like object. So what exactly could this be pointing to?
View 2 Replies
View Related
Apr 28, 2013
I want to use this array as part of my class. I have tried several different angles trying to get it to work but with out success. I have been checking to see if it works by simply using "cout << dayName[3];" It is printing nothing at all. What is the proper way to initialize this array of strings?
First I tried this:
const string dayName[] = {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"};
then I tried this:
const string dayName[7];
dayName[0] = "Sunday";
dayName[1] = "Monday";
dayName[2] ="Tuesday";
dayName[3] ="Wednesday";
dayName[4] ="Thursday";
dayName[5] ="Friday";
dayName[6] ="Saturday";
My implemetation file code and my header file code is here (header first):
//dayType.h, the specification file for the class dayType
#include <iostream>
#include <string>
using namespace std;
class dayType{
[Code] .....
View 4 Replies
View Related
Mar 16, 2012
I'm using a singelton class ( is this coded correctly?), and from the main class, im trying to initiliaze my Direct2D class, only I do get this error:
error C2143: syntax error : missing ';' before '.'
These lines gives it:
CSingleton.GetCDirect2DInstance()->CreateDeviceIndependentResources();
singleton.hpp
Code:
#ifndef CSingleton_h__
#define CSingleton_h__
#include "CDirect2D.hpp"
class CSingleton {
public:
static CDirect2D* GetCDirect2DInstance();
[Code] ....
View 9 Replies
View Related
Dec 3, 2014
A have two classes, one inheriting the other, and the parent class being abstract (I plan on adding more child classes in the future). For reasons I won't bother mentioning, I'm making use of an STL container as a way for me to access all of the child objects in the heap. I've done so by making use of a map, with key type int and value type being a pointer to the parent class:
//PARENT.H
class Parent {
protected:
static int n;
static std::map<int, Parent*> map;
public:
virtual void pureVirtual() = 0;
[code]....
The Problem:In line 5 of Parent.cpp, initializing the value of the element to new Child won't work, as according to the compiler, the Child class hasn't been declared yet, and including Child.h into the Parent.h only opens an even bigger can of worms.I also can't initialize it as new Parent, seeing as the parent class is an abstract one.
The Question:Is there a way I can initialize the static map properly. Making the Parent class abstract is not an option.
View 3 Replies
View Related
Feb 20, 2012
class Base
{
char * ptr;
public:
Base(){}
Base(char * str)
[code].....
Obj1 is a derived class object where base class char pointer is initialized with "singh" and derived class char pointer is initilized with "sunil". I want to create Obj2 out of Obj1. Separate memory should be created for Obj2 char pointer (base part and derived part as well) and that should be initialized with the strings contained in Obj1.
Here the problem is: Derived class part can be initialized with copy constructor. How to initialize the base class char poniter of Obj2 with the base class part of Obj1. char pointers in
both the classes are private.
I tried using initializer list but could not succeed.
Is there some proper way to do this?
View 4 Replies
View Related
Aug 3, 2013
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?
View 1 Replies
View Related
Feb 9, 2013
I am trying to display a variable from a class function the code works in debug but the variable is not displayed. Here is my code so far.
#include <iostream>
#include <string>
using namespace std;
class dayType {
public:
string day;
void setday(string);
[Code] .....
View 2 Replies
View Related
May 6, 2014
I'm trying to change the values of some instance variables in my Controller Class so that when the user inserts values into main class it changes for Controller.
class Controller {
public:
Controller();
~Controller();
double PCFreq;
__int64 CounterStart;
[Code] ....
The user should be able to choose which foo the want to use. So I create an object of controller in main like this
Controller* con = new Controller()
Now my issues is, when I take user input (an integer) and try to do this
con->choice1 = choice1;
only the object of con's choice1 is = to user input.
However back at the class for Controller, choice1 hasn't received a value.
I can't initialize through Controllers constructor because I get the user input through a switch statement and the range of con would only be as far as the case.
View 2 Replies
View Related
Apr 16, 2014
I am not able to access the class variable noof_vertex in the function merge , the error is the variable is private . below is the code :
#include <iostream>
#include <ctime>
#include <cstdlib>
[Code]....
View 1 Replies
View Related
Mar 21, 2012
Code:
class CObjects {
int m_CurrentTime;
int m_Steps;
AStarList* OPEN;
AStarList* CLOSED;
std::vector<AStarNode *>solution;
[code]....
CCB is derived from CrowdEntity and in turn is derived from CObjects Inside CObjects, I declared AStarList *OPEN; Why would howmany become garbage (cdcdcdcd) when I reference it in GetBestNode()
View 9 Replies
View Related
Apr 8, 2015
C++
Create a Triangle class that has the following member variables:
side1 - a double
side2 - a double
side 3 - a double perimeter area
The class should have the following member functions:
- default constructor that sets the value of all 3 sides of a triangle to 0.0
- a constructor with arguments that accepts values for the three sides of a triangle (member variables) as arguments
- setDimensions - a function that allows the value of the three sides to be entered by the user through the keyboard
- testSides - a function that determines if the 3 values entered can actually be the sides of a triangle. If they do not create a triangle, print the values entered and an appropriate message
--The sum of any two side lengths of a triangle must always be greater than the length of the third side: so side 1 + side 2 > side 3 and side 1 + side 3 > side 2 and side 2 + side 3 > side 1 ( all three must be true for the 3 values to make a triangle)
- getSide1 - a function that returns the value of side 1, getSide2 - a function that returns the value of side 2, getSide3 - a function that returns the value of side 3
- getArea - a function that returns the area of a triangle: The formula for the area of a triangle (when the height is not known) is: A = sqrt (p(p-side1)(p-side2)(p-side3)) where p = (side1+side2+side3)/2
- getPerimeter - a function that returns the perimeter of a triangle: Perimeter = side1 + side2+ Side 3
- A displayTriangleInfo function that displays side1, side2, side3, area, and perimeter for a triangle object.
After testing your code for a single object, create an array of 5 triangles. Use a for loop and the setDimensions function to allow the user to set the values for the 3 sides of a triangle, test the vales entered to determine if the 3 create a triangle. If they do create a triangle than use the getArea and getPerimeter functions to calculate the Area and Perimeter for the triangle and use the displayTriangleInfo function to display all of the data for that triangle. If the three values do not create a triangle then print the 3 numbers entered and an appropriate message. In either case the loop should then move on and get the data for the next triangle from the user.
View 7 Replies
View Related
Jun 22, 2013
Suppose I have two classes, MyClassX and MyClassY, each with two member variables, as defined below. I create an object instance of each class, and then create a pointer to each member variable for each object:
Code:
class MyClassX
{
public:
int a;
double b;
MyClassX(int _a, double _b)
[code]....
After converting the hexadecimal to decimal, it appears that with MyClassX, pxb is 8 bytes from pxa, whereas for MyClassY, pya is only 4 bytes from pyb. This makes sense for MyClassY, because the first member variable to be stored is an int, and so will occupy 4 bytes. However, why should this be any different for MyClassX, which also has an int as the first member variable, so shouldn't this also occupy 4bytes?
The reason I have come across this problem is that I am looking into streaming objects to memory and then loading them again. (I know boost can do this, but I am trying it out myself from scratch.) Therefore, this is causing an issue, because I cannot just assume that the size of memory occupied by an object is just the sum of the sizes of its member variables. MyClassX is 8 bytes larger than MyClassY, even though the intuition is that it should only occupy 4 bytes more due to a double being replaced by an int.
View 4 Replies
View Related
Mar 1, 2013
Here's a bit of code:
CvClimateInfo::CvClimateInfo() :
m_iDesertPercentChange(0),
m_iJungleLatitude(0),
m_iHillRange(0),
m_iPeakPercent(0),
[Code] ....
does this means that these variables are initialized with the values between parentheses?
View 2 Replies
View Related
Dec 14, 2014
I'm trying to implement Tarjan's Strongly Connected Components Algorithm in C++. Here's how I gotten so far:
void tarjan(vector<Vertex>& G){
index = 0;
while (!S.empty()) S.pop();
[Code]....
Here's an example graph for the algorithm to run: [URL]
Here's the first part of the output of the program: [URL]
all the index & lowlink values of the nodes are set to -1 in the beginning. global index value is set to 0. My problem is, the algorithm starts running on Vertex X-4. It runs the instruction X-4.index=0 & X-4.lowlink=0 then it calls itself with the paramater of node X-1. it sets X-1's index & lowlink values to 1. then it calls itself for X2. then it checks whether node X-4 has the index value <0 or not. Even though we set the value of X-4 to 0 in the first run, it still sees X-4.index as -1.
View 1 Replies
View Related
Jul 31, 2013
I have written a class "FileSet " in program's Document class.
This class contains other Four classes as
"Machine1" , "Machine2", "Machine 3" and "Machine 4".
Now my problem is Machine 1 can not access variables from Document class or other variables from FileSet.
How to access them ?
View 9 Replies
View Related
May 13, 2014
I've got this sorting program that uses variables from another class but I'm not sure why its not recognizing it. I'm getting an error length and list not declared in this scope.
#include <iostream>
#include "arrayListType.h"
using namespace std;
template<class elemType>
class orderedArrayListType: public arrayListType<elemType> {
[Code] ....
View 1 Replies
View Related
Feb 22, 2013
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?
View 2 Replies
View Related
Nov 21, 2013
I'm unable to access private variables belonging to the object class Date, which my overloaded >> operator is a friend of. I can't see anything in my code that would be causing this error. The .h file and the definition of the problematic overloaded operator from the implementation file are below:
#ifndef DATE_H
#define DATE_H
#include <string>
using namespace std;
class Date {
public:
// Initializes a date to the default value of January 1, 1970.
[Code] .....
The error message states that the vars (month, day, year) are declared as private in the header file and then a reference is made to the lines where I attempt to access these in the .cpp file and it reads: "in this context".
View 5 Replies
View Related
Aug 22, 2013
I can't get my code to compile, i need to read in lines from a file and store them in variables. Then i have to construct instances of my class for how many lines there are in the file and take those variables into them.
I'm getting this error :
"a2.cpp:40: error: cannot convert `Employee' to `Employee*' in assignment"
#include<iostream>
#include<string>
#include<fstream>
void displayInfo();
using namespace std;
class Employee{
[Code] .....
View 1 Replies
View Related
Mar 6, 2015
I am making a tictactoe program that requires me to have a 3 by 3 two dimensional array of integers, in which the constructor should initialize the empty board to all zeroes. The program complies, but it keeps outputting garbage values and i'm not entirely sure why, My print function isn't complete yet, since I want to print out the array in a tic tac toe format, but i'm more concerned with why it's printing garbage values, here is my code:
Code:
// header file
#include <iostream>
#include <array>
[Code] ....
View 7 Replies
View Related
