I'm trying to implement a vector class in C + +. However when I go to actually run the main, it generates an interrupt operating system.
MAIN.cpp
#include "header.h"
int main() {
// Definisco le istanze delle classi
vettore <int> vet;
vettore <int> vet2;
vettore <int> vet3;
[code].....
To get a value I would always use setter and getter. Would it be much better (performance) to use vector subscript operator overloading? And does vector subscription operator overloading require a size for the vector?
vector<int> v(10);
because otherwise, it doesn't work...
Recently, i successfully overloaded postfix operator to class counter by using Object and Class. Now, i want to overload same postfix operator to Inheritance. I created my code and generated in compiler. But, my compiler signaled me uncommon error(saw first time) and i couldn't generate any idea where my actually mistake is.
Here is my Code which objective is to count the number increasingly or decreasingly as per object created of CountDn class.
Code:
#include <iostream>
using namespace std;
class Counter // base class
{
protected : // NOTE : Not Private
unsigned int count;
[Code] ....
Error :|41|error: no 'operator++(int)' declared for postfix '++', trying prefix operator instead|
|42|error: no 'operator++(int)' declared for postfix '++', trying prefix operator instead|
|42|error: no match for 'operator=' in 'c2 = c1.CountDn::<anonymous>.Counter:perator++()'|
|44|error: no 'operator--(int)' declared for postfix '--', trying prefix operator instead|
So i am having troubles with operator overloading in inherited class. Basically, it doesnt work. Consider this:
Code:
class A {
public:
A() {
x=0;
z= new int;
[Code] ....
Some how the copy constructor of a is improperly executed - the pointer is copied over, not re-created. As a result, the destructors crashes due to double-free.
*/
B bb = b; //doesnt work
B bbb(b); //doesnt work
B bbbb(b, 0); //works
}
Above code shows the problem well. The "official" copy-constructor wont work - it copies over the pointer directly, and doesnt create a new one as it should. However, if i provide my own pseudo-copy-constructor that works. But ofcourse it's just a cheap work around - and wont actually work in real code (STL).
compiler is VS2008SP1.
#include<iostream.h>
#include<conio.h>
class sum {
int a,b,ans;
public:
void geta() {
cin>>a;
[Code] ....
Write c/c++ code of overloading ^operator in complex number class.
If we have two objects of complex number class as fellows,complex obj3 =obj1 ^obj2 ;
Obj3 reak and imaginary pars will be ,
Obj3.real = (obj1.real)obj2.real
And
obj3.img = (obj1.img)obj2.img
I am creating a class called time and we've had to do operator overloading for <, > , <=, >=, ==, !=, ++, --, >>, <<, * , +, and -.
Well I have done and error checked them all. The only one I cannot seem to get right is the minus and its because of the error checking. I am having issues with times like this
t1 = 0:0:2:3
t2 = 0:0:1:4
t1 - t2 should equal 0:0:0:59 but it returns 0:0:1:-1.
(days:hours:minutes:seconds)
I need it to check for all cases and I just do not know how. Here is the code I have so far:
time operator- (const time& x, const time& y){
time subtract;
subtract.days = x.days - y.days;
subtract.hrs = x.hrs - y.hrs;
subtract.mins = x.mins - y.mins;
subtract.secs = x.secs - y.secs;
[Code] .....
I wrote a simple Complex Class and overload input/output and +/- Operators in it!But there is something that doesn't work correctly!I can print an object of that class but I can't print sum of two object or something like that!
Code:
#ifndef COMPLEX_H
#define COMPLEX_H
#include <iostream>
using namespace std;
class Complex {
friend ostream & operator<<(ostream &, const Complex &);
[Code] .....
cout << c3 is Working fine But cout << c1 + c2 is not giving me correct output!
I have a list of numbers in an array created by a class template
Code:
#include <iostream>
#include <fstream>
#include <string>
#include <iomanip>
using namespace std;
const int CAPACITY = 20;
template <class T>
class A
[code].....
I need to create a class vector as a template and define operations on vectors.
And this is what I made.
#include<iostream>
using namespace std;
template<class T>
[Code].....
class A {
// is abstract
};
class B : public A {
// ...
};
[Code] ....
[Code] ....
main3.cpp: In member function ‘FooB& FooB::operator=(const FooC&)’:
main3.cpp:46:44: error: expected ‘(’ before ‘other’
main3.cpp:46:49: error: no matching function for call to ‘Foo<C>::Foo(const FooC&)’
main3.cpp:46:49: note: candidates are:
main3.cpp:19:2: note: Foo<T>::Foo() [with T = C]
main3.cpp:19:2: note: candidate expects 0 arguments, 1 provided
main3.cpp:16:25: note: Foo<C>::Foo(const Foo<C>&)
main3.cpp:16:25: note: no known conversion for argument 1 from ‘const FooC’ to ‘const Foo<C>&’
Is there any way to make it work?
I am making a vector class and am having some problems creating the overloaded arithmetic operators and assignment operators.
Here is an example of my "+=" code as it stands the errors are similar/the same for the other operators except "=" operator which works fine:
Vector3& Vector3::operator+=(const Vector3 &rhs) {
Vector3 tmp = *this;
Set(tmp.getX() + rhs.getX(), tmp.getY() + rhs.getY(), tmp.getZ() + rhs.getZ());
return *this;
}
I have tried a lot of different approaches ad always get the error:
error: passing 'const Vector3' as 'this' argument of 'double Vector3::getX()' discards qualifiers
error: passing 'const Vector3' as 'this' argument of 'double Vector3::getY()' discards qualifiers
error: passing 'const Vector3' as 'this' argument of 'double Vector3::getZ()' discards qualifiers
I designed a class template to create unique arrays. I was able to successfully input data to and output data from my array objects, irrespective of the datatype. However, I can't for the life of me fathom why my overloaded assignment operator worked perfectly well only for integer datatype and not for double/string datatypes.
Here is the class definition:
template <class dataType>
class myArray {
public:
void setArrayData();
[code]....
And here is the definition of the overloaded assignment operator:
template<class dataType>
const myArray<dataType>& myArray<dataType>::operator=(const myArray<dataType>& rightArray) {
int i;
if(this != &rightArray) {
delete [] arrayPtr;
[Code] ....
And here is my main function that tests the operations on objects of the class:
int main(){
//object declarations
myArray<double> list(5); //a single-parameter object declaration of class myArray
myArray<double> myList(2,13); //a two-parameter object declaration of class myArray
[code]....
The problem I'm having starts from where the assignment operator is being tested: for double and string datatypes, the upper input/output section works fine, but the assignment section freezes the display until the program execution is manually terminated!
How to assign the array in object Q to the 12 months, Dec through Jan. I then have to sort the array and display the strings from Jan to Dec.
// main.cpp
#include <iostream>
#include <string>
#include <cstring>
#include <ctime>
#include <algorithm>
using namespace std;
// Declare template class
template <class T, int n>
[Code] ....
I'm trying to get the command pattern for template classes down. I'm just having a hard time implementing one part of the code. I can't figure out why both the method being passed and the type accepted are not the same type.
SimpleCommand class
template <class Receiver>
class SimpleCommand : public Command {
public:
typedef void(Receiver::*Action)();
SimpleCommand(Receiver *r, Action a) :
[code].....
And their instantiation
MyClass *receiver = new MyClass;
Command *aCommand =
new SimpleCommand<MyClass>(receiver, &MyClass::Action);
aCommand->Execute();
I got an array class, but I'm getting this error:
Error1error C2953: 'Array2D' : class template has already been defined
Here's the code:
#include "Tools.h"
template <typename T>
class Array2D {
T** arr;
int xSize;
int ySize;
[Code] .....
When I do this:
// header file:
#include <list>
using namespace std;
class myClass {
list<int> myMethod();
};
// cpp file:
list<int> myClass::myMethod() {
}
In the cpp file, 'myMethod' is underlined in red and when I hover over it, it says:
"std::list<int, std::allocator<int>> myClass::myMethod()
Error: declaration is incompatible with "<error-type> myClass::myMethod()""
But when I make it as a standalone function, outside a class, with no pre-declaration, there is no problem.
I made a simple binary tree then decide to try out threads too. I got the following error:
call of an object of a class type without appropriate operator or conversion
Code:
#include "Tree.h"
#include <iostream>
#include <thread>
void main(void){
[Code] ....
I am having a hard time figuring out why the error exists. I tried adding the new operator but that did not work.
In this below example:
class Point {
private:
double m_dX, m_dY, m_dZ;
[code].....
In that situation, << does not call the overloaded function, but rather calls the << method defined in the i/o library, which prints a message to the controlling terminal. So once it prints the message to the terminal, it then returns the out instance. Why return the out instance rather than a boolean like true? As you can see from the example, once the message is printed to terminal, out is not used anymore.
I am working on this assignment...
Code:
#include <iostream>#include <iomanip>
using namespace std;
class Score
{
private:
// Value at which we'll shift digits from million_counter to billion_counter
static const int THRESHOLD = 1000000000;
[Code] ....
It gives the errors:
line 105 error: million_counter was not declared in this scope
line 106 error: normalizeScore was not declared in this scope
line 110 error: million_counter was not declared in this scope
and more of that until
line 170 error: no match for 'operator<<' in 'std:perator<< <std::char_traits<char> >((* & std::cout), ((const char*)"a+b is ")) <<operator+((*c(const Score*) (& a)), (*(const Score*)(& b)))'
I thought that because i declared friend functions, they would be able to access the private variables of the class.
Well... I observed, as a non-professional programmer that "overloading operators" has some strict rules and some conventions... so any operator can differ from another. In order to have a clearest idea, I'd like to ask you to specify, for every operator, the correct (or best) way to overload it.
There are cases where you define &operator and cases where you define operator (without "&"). There are cases where operator are defined as "friend" inside class, and other cases where operator is declared externally.
example: ostream &operator<<
(why it uses & ??)
So can we have a summary for all kind of operators?
I'm trying to overload operator<<, but I get an error saying 'ostream' does not name a type. Am I forgetting to declare something else? ostream& operator<< (ostream& out, Struct &b);I made sure to #include <iostream> too.
View 1 Replies View RelatedI am having a bit of an issue figuring out how to operator overload with chaining. I have this as my operator= function (Its for linked lists)
WORD & WORD::operator=(const WORD & Org){
cout << "
operator= has been called WITH CHAINING
";
character *p = front;
[Code] ....
I want to be able to do X = X = X where X is of class WORD, but it errors when that line is called. And by error, I dont mean a written error, it just compiles, then says 'MSVC has stopped working' on a new pop up.
I want to implement operator overloading for +=, so that the following arethmetic is possible for matrices: matrix += matrix
Here is how I have defined it in matrix.h
#ifndef MATRIX_H
#define MATRIX_H
#include <cassert>
#include <iostream>
#include <iomanip>
using namespace std;
template <class T> class Matrix;
template <class T> Matrix<T> operator+= (const Matrix<T>& m1, const Matrix<T>& m2);
[code].....
How do I implement this correctly?
How to finish these two remaining operator overloading functions
Also, "contents and NumItems are private"
Code:
Bag operator+ (const Bag& b1, const Bag& b2);
//Postcondition: the bag returned is the union of b1 and b2.
ostream& operator<<(ostream&, const Bag&);
//Overloading operator <<
[Code] .....
I have a date class and i overloaded operator >> to accept input in dd/mm/yyyy format. if i enter the wrong date format my program will crash. How do i do exception handling for this? How should i do the try part? and for catch, I'll just catch a date class variable?
Code:
void operator >> (istream &is, clsDate &date) {
string inputDate;
is >> inputDate;
int mm = stringToNumber(inputDate.substr(3,2)); // read 2 characters from character number 3 start
int dd = stringToNumber(inputDate.substr(0,2)); // read 2 characters from character number 0 start
int yy = stringToNumber(inputDate.substr(6,4)); // read 4 characters from character number 6 start
[Code] .....
