C++ :: Limit In Number Of Objects Of Class?
Jul 8, 2013Is dere is any limit in number of objects of a class?
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C++ :: How To Limit The Number Of Function Call
Apr 23, 2013In my program, i have a function, example: bool open(string szString); this function i have known it's fix address, example: 0x12345678 Because of my computer which has low capability, if this function is called 1000 times per second it will be hanged, slow. So i want limit the number of function call down to 500 times per second. how will i do with C/C++?
View 2 Replies View RelatedC++ :: Limit Number Of Count Error
Jul 7, 2014I was wondering how to limit error message to one only.
For example
cin.getline(stringname,7);
for(int i=0;i<size;i++){
if(strcmp(stringname, "hello")=0)
cout<<"Found!"<<endl;
else
cout<<"not found"<<endl;
}
not found
not found
.......
I want to get only once not found
C++ :: Limit Number Of Flottant To Get Equal Numbers?
Feb 26, 2014I calculate two numbers "R1",R2"
when i make
cout<<R1;
cout<<R2
i get
R1=51,9151
R2=51,915
when i make
Code: if (R1>R2) cout<<"i am here" he print the message
but they are equal. how i made limit the number of flottant to get equal numbers?
C/C++ :: Limit Access To Class Member Functions
Feb 28, 2014Suppose I make a class, something like having the constructor being invoked first makes sense, I don't have a problem with that. But, how could I limit access to functions until certain functions are called? Perhaps this isn't built into the language so you can't. And maybe this problem never comes up. For example if you have a set() and get() functions, if they are both public functions, there doesn't seem to be a way for the compiler at least now if set() never gets called you shouldn't call get(). I just see this as error prone if you need to use libraries, you have to know not to do it from documentation instead of something the compiler can check.
View 11 Replies View RelatedC++ :: Deleting Array Of Derived Class Objects Through Base Class Pointer
Mar 21, 2015In this book, item 3 is about never treat arrays polymorphically. In the latter part of this item, the author talks about the result of deleting an array of derived class objects through a base class pointer is undefined. What does it mean? I have an example here,
Code:
class B
{
public:
B():_y(1){}
virtual ~B() {
cout<<"~B()"<<endl;
[Code] ....
This sample code does exactly what I want. So does the author mean the way I did is undefined?
C++ :: Creating Array Of Pointers To Base Class To Point To Derived Class Objects Dynamically
Jan 16, 2013Please consider the following code :
#include <iostream>
using namespace std;
class superclass;
class subclass1;
class subclass2;
[Code] ....
As you can see I want to create a dynamically allocated storage of references to a parent class each of which can then point to a child class, how ever I do not know how to extract the child class out again from that array so i may access its variable b.
C++ :: Initializing Inner-objects Of Base Class From Driven-class Constructor
Jan 6, 2015Let'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 .
C++ :: Where To Define A Large Number Of Objects
Jan 20, 2013I am trying to run a simulation with a large number of objects (mainly arrays and vectors). I am not sure where shall I define my objects: inside or outside of the main() function, like the following two structures:
(1) ---------------
//main.cpp
int main(){
array<double, 1000> a_1 = {};
array<double, 1000> a_2 = {};
......
func_1(a_1, a_2, ..., a_100);
return 0;
}
[Code]...
I know there is a question about scope. But besides this question (which seems have no difference between these two structures here), is there any difference in terms of execution performance or security issue?
C++ :: How To Find The Number Of Objects Without Loop
Nov 25, 2013how i can find the 5 without loop?
vector<int>i;
vector<int>j;
i.push_back(1);
i.push_back(2);
j.push_back(3);
j.push_back(4);
j.push_back(5);
[Code]...
C++ :: How To Use Class With Array Of Objects
Oct 12, 2014class FlashCard {
public:
int a,b;
void PrintCard(void);
int CorrectAnswer(void);
};
void SwapFlashCard(FlashCard &a,FlashCard &b)
[Code]....
Why does Xode warn me that Type'FlashCard'does not provide a subscript operator on line 22,23,29 and 30?
C++ :: Add Three Objects Of A Class Matrix
Apr 9, 2014I have been working on an assignment where I have to add three objects of a class Matrix. The class should have the flexibility to add more than two oprands without changing any operand on Left hand side of the '=' operator.
Matrix obj1, obj2, obj3, obj4
Obj1=obj2+obj3+obj4
I am using the following code for this
Matrix Matrix::operator + (Matrix &obj) {
if((this->Columns == obj.Columns) && (this->Rows == obj.Rows)) {
for(int i=0;i<obj.Rows;i++)
[Code] .....
the problem is that it is just adding only 2 operands. How can I add more?
C++ :: Array Of Class Objects
May 13, 2014I need an array of class objects but am unsure of how one might accomplish this. I have so far...
//element class driver code
Element Arsenic(lowCeiling, highCeiling);
Element Cadmium(lowCeiling, highCeiling);
Element Chromium(lowCeiling, highCeiling);
Element Copper(lowCeiling, highCeiling);
Element Lead(lowCeiling, highCeiling);
Element Nickel(lowCeiling, highCeiling);
Element Molybdenum(lowCeiling, highCeiling);
Element Mercury(lowCeiling, highCeiling);
Element Selenium(lowCeiling, highCeiling);
Element Zinc(lowCeiling, highCeiling);
Element metal[10] = {Arsenic, Cadmium, Chromium, Copper, Lead, Nickel, Molybdenum, Mercury, Selenium, Zinc};
Could the array be created in this manner or is that illegal code?
C++ :: Class Objects In A Vector?
Mar 16, 2013So I'm trying to store class objects in a vector:
#include <iostream>
#include <fstream>
#include <sstream>
#include <string>
[Code]....
1. Am I storing it correctly?
2. How would I access the stored data, say, if I wanted to compare it to other stored data or COUT it?
C++ :: Class Admin - Array Of Objects
Jun 26, 2013What I want to do is have an admin class which will hold all the employee objects, can add them, list and calculate salaries. I'm trying to make array of objects, not sure if it's right
here is the code
Code: #include <iostream>
#include <string>
using namespace std;
class Employee {
public:
Employee(string name, short type, int salary)
[Code] .....
C++ :: How To Loop Through A Vector Of Class Objects
Mar 22, 2013For a beginners C++ lab, I have a base class Employee and two derived classes HourlyEmployee and SalaryEmployee. In main, I have a vector defined as vector <Employee *> VEmp; It's then passed to a function to get the input, which works fine. But what I'm struggling with is another function with the header "printList(const vector <Employee *> & Ve)". It's supposed to loop through the vector and call the appropriate printPay function, which is a seperate print function inside each derived class. How do I loop through the vector and print it out? I was trying to do a for loop and something like "Ve[i].printPay();", but that doesn't work. So how would I do it?
Here's some snippets of the relevant code.
class Employee {
....
virtual void printPay() = 0;
};
class HourlyEmployee : public Employee {
[Code] ....
C++ :: How Class Objects Stored In Memory
Aug 23, 2014For example when I have:
Class A{
B objectB;
};
Now when I instantiate the object of class A like:
main(){
A objectA;//option 1
A* pObjectA = new A();// option2
}
How is objectB stored in memory (stack heap etc.) for both options??
C++ :: Cout And Cin Objects Of Iostream Class
Feb 17, 2013i ran the following code in the latest version of code::blocks and it tells me that the objects cout and cin are not declared in this scope. what is the problem?
I used to use Turbo C++ 3.0 and i had no problem whatsoever with that compiler. But now i am trying to move to code::blocks but it is proving very very hard as all the standards have been changed.
I am a school student and thus, we had been told to practice on Turbo C++ 3.0 and now i am unable to unlearn it. Also, if i use printf in place of cout there is no error but i want to use cout as it is what i am comfortable working with.
#include<fstream>
#include<conio.h>
int main() {
using namespace std;
char name[20];
[Code] ....
Is there some document to which i can refer so as to get the latest C++ standards which is C++0x i believe?
C++ :: Use Array To Store Class Objects?
Feb 11, 2013So starting with the Item.h file :
#ifndef ITEMH
#define ITEMH
using namespace std;
class Item
[Code]...
I think I'm getting the wrong idea about strings. I thought I could add data just by using '+=' but apparently not.
C++ :: How To Make Array Of Objects For Class
Aug 18, 2013class A {
Public:
A (int);
A(int,int);
int get (int,int);
};
C++ :: Create Objects From Abstract Class
Oct 13, 2013I am working on a project that requires me to create objects from a abstract class that has 2 child classes (that need to be derived). Any examples on how to do this? I looked online and the examples were pretty vague. the main error that I am getting is when I make a temp object with & in front of it (such as Employee &genericEmp) it throws a must be initialized error.
View 6 Replies View RelatedC++ :: How To Compare Values Of Two Objects Of Same Class
May 27, 2013Running into a snag in my program. I can't seem to figure out how to have an object of a class be able to look at all the other objects of its own class.
Reasoning being, I'm working on a game with multiple ships flying around in the same space. Each ship is a class.
Each ship has an x and a y, and needs to compare the angle and distance of other ships' x and y coordinates to see if they're visible on the same screen.
How to tell an object to look at objects of its own class.
Here's some code:
common.h
#ifndef COMMON_H_INCLUDED
#define COMMON_H_INCLUDED
int dist(int x1, int y1, int x2, int y2);
int get_info(int which);
[Code] ....
Basically, I just don't know how to properly write a function, call, or how to get the info I need, to the Player::get_closest() function so that it can see the other play objects.
C++ :: Dynamically Create Class Objects?
Nov 3, 2013regarding dynamic vector.
Shape2DLink.cpp
void Shape2DLink::InputSensor()
{
string shape,type;
[Code]....
So i'm actually using polyphormism for calculating the area of the cross and other shapes. so how do I actually make use of dynamically create an object this way?
do I create them in my Shape2DLink or in my individual child classes?
C++ :: Class With A Vector Of Objects As Attribute
Dec 9, 2013I'm having the same problem : [URL] .....
Though, my vector isn't one of int, it is a vector of objects from another class and NetBeans won't compile it.
#include <cstdlib>
#include<vector>
#include <string>
#include<iostream>
using namespace std;
class estoque{
[Code] .....
C++ :: Adding Two Objects Of Class (Matrix)
Feb 13, 2013I am trying to add matrices a and b. I am getting an error in the "add" function, probably because I have m[i] in it, and m is not an array. What is the correct way of writing the "add" member function here?
Also, although the "read" and "write" member functions of the class are working just fine, do you think there is a better way of writing them?
Code:
#include <iostream>
#include <cmath>
#include <iomanip>
using namespace std;
const int rows=3;
const int columns=3;
[code].....
C++ :: Thread Safe Class - Queue Of Objects
May 7, 2013I am new to C++ programming and i have a small assignment.
How to implement a thread safe class to manage a queue of objects. Accessing the front of the queue should be a blocking operation when the queue is empty.