C++ :: Can A Friend Function Work For Two Classes?
Mar 23, 2013If yes then how?
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C++ :: Friend Functions And Classes Not Permitted To Data
Dec 29, 2013I have a situation: I have a class character
class Character;
class Village;
class Character {
public:
//Functions
void charGen(); //Character creation
[Code] .....
According to the Friendship and Inheritance tutorial [URL] ...., that code should work, but it doesn't. I am given an error: undefined reference to questsCompleted
The compiler I am using is Code::Blocks ....
Visual C++ :: Friend Classes In Separate Header Files?
Nov 25, 2012I am struggling to enable friendship between two classes in separate header files for a banking program.
I am attempting to get the Person class to use variables from the Account class. Heres what I have so far.
ACCOUNT.h:
Code:
#include<iostream>
#include<fstream>
#include<cctype>
#include<iomanip>
#include <string>
#include <math.h>
#include <windows.h>
#include <vector>
#include "Person.h"
using namespace std;
class person;
[code].....
C++ :: Does Prototype Of Friend Function Has No Value?
Mar 30, 2013[URL] ..... Prototype is commented.
[URL] ..... Prototype is included.
both give the correct output. Why?
C++ :: Operator Overloading Using A Friend Function
Jul 24, 2013What is the role of friend function in this program? Is it even executed here?
#include <iostream>
using namespace std;
class loc {
int longitude, latitude;
public:
loc() {} // needed to construct temporaries
[Code] ....
C++ :: Friend Function Can't Able To Access Private Member
Jan 21, 2015Am trying to write table object into file. Here's the source code
.hpp file
class Table {
private:
int table_no;
std::string table_type;
bool engaged;
std::time_t start_time;
double total_sec;
[Code] ....
When i compile the above code i get the following error...
table.hpp: In function ‘std::ifstream& operator>>(std::ifstream&, Table&)’:
table.hpp:19:7: error: ‘int Table::table_no’ is private
table.cpp:91:12: error: within this context
table.hpp:20:15: error: ‘std::string Table::table_type’ is private
table.cpp:92:12: error: within this context ...........
C/C++ :: Overload Operator With Friend Function Using Constructors
Dec 26, 2014I want to overload prefix and postfix increment(++) operators with friend function. I also have to use the constructors for this. How can I do this? in C++
View 4 Replies View RelatedVisual C++ :: Friend Class And Pointer Function
Mar 9, 2013I need understanding this block of code, particularly this line : *getLeftChild() { return this - _child; }
Code:
public class UpperNode {
BOX _box;
int _child;
FORCEINLINE UpperNode *getLeftChild() { return this - _child; }
...
};
Here I have this function:
Code:
void
UpperNode::visulization(int level) {
if (isLeaf())
_box.visulization();
else
if ((level > 0)) {
[Code] .....
It also makes calls for "getLeftChild()";
But I see that getLeftChild expects function pointer, and I absolutely have no clue where "this" comes from inside function body.
(return this - _child) - "this" has to be integer.
Or, if we gave pointer, and "this" is referring to some UpperNode, then I can't understand to which one, I have no UpperNode array defined or something. So if this functions is actually scaling pointer address, then scaling where to? I could comprehend it, if I had some array of UpperNodes, but not just class. I have UpperNodes array defined in other friendly class, but don't think they are related .....
C :: Function That Will Work For Both Dynamic And Static Implementations Of A Function To Get Transverse Of Matrix
Feb 11, 2013i need a function that will work for both dynamic and static implementations of a function to get the transverse of a matrix. so far, i have this
Code:
matrix transpose(matrix m)
{
int row, col;
row = m.com_dim;
col= m.row_dim;
}
[code]....
this works well with my static implementation, but when i try it in dynamic it gives me errors. the function has to be the same for both dynamic and static implementation
C++ :: Template Function Don't Work As Inline Function?
Mar 8, 2014I have this:
string input;
unsigned short choice;
...
istringstream valid(input);
...
if(!(valid >> choice))
{
//some error
}
Ok. My code is almost 1000 lines, and I have splited some functions in headers. But the same function doesn't work:
template <typename T> bool valid_input(const string& input, T var)
{
istringstream valid(input);
return (valid >> var);
}
You can check it here: [URL] The output is correct, but in my machine with C++11, MinGW 4.8 (64 bit in a 64bit-Windows8), the output is incorrect. Why?
If you want more specific info, the problem is that I use input, I think. I use std::getline(std::cin, some_string).
C++ :: Print Function Does Not Work Properly
May 21, 2013This is my code for submitting students but when i use search function the course member is empty
Code: #include "windows.h"
#include "iostream"
#include <io.h>
#include <sstream>
#include <conio.h>
#include <stdlib.h>
#include <iostream>
#define SIZE 5
using std::cout;
using std::cin;
using namespace std;
int menu();
[code].....
C :: Qsort Function Won't Work Properly
Mar 20, 2013i am facing some problem with qsort() function it work well if the last element of array is larger then the 2nd last element. But in case if last element of array is smaller then the 2nd last it will sort the whole array and remains the last as it is. For example
Code:
int group_id_local[max_j]={2,1,4,5};// it work fine, output should be {1,2,4,5} but if i have this one
int group_id_local[max_j]={2,1,4,3};
// output should be {1,2,4,3}
/* COMPARE FUNCTION FOR USING QSORT()*/
int cmpfunc (const void* a, const void* b)
{
if (*(int *)a < *(int *)b) return -1;
if (*(int *)a > *(int *)b) return 1;
return 0;
[Code]....
why it will not sort the last element?
C++ :: BST Node And Count Function Don't Work?
Dec 2, 2013I have to do a BST project for school and I am almost there. Here is the code:
BINARY_SEARCH_TREE.cpp
#include "stdafx.h"
#include "genBST.h"
#include <iostream>
using namespace std;
[Code].....
When I run the program, it compiles correctly but does not give any output. I'm not sure what else to do. I've tried changing up the code in nodeCount(), leafCount(), NodeCount(), and LeafCount(). I've tried adding a count variable to both nodeCount() and leafCount() but that didn't work. If I fiddle with the functions, I get a whole mess of errors. Currently, the code is stable but just won't output what I want it to.
C# :: Can't Get Math (Sine) Function To Work
May 21, 2014I'm having trouble with getting a sine function to work. All variables are defined earlier in the same section. I have the code in a button (where I figured it would go) but I get the following error:
WindowsFormsApplication2.Math does not contain a definition for 'Sin'
For reference, I am using Microsoft Visual Studio Express 2013, and am coding a Windows Forms Application.
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
[Code] ....
I've tried other functions as well (abs, sqrt, etc.) to no avail, as Math only seems to pop up with two options: Equals and ReferenceEquals.
C++ :: Make A Function Integrate To Work With Other Functions Given
Mar 10, 2013We have to make a function integrate to work with the other functions given. I had it working before but I would only get all -4 as my answers but only the first one should be -4. what should more or less be put in my integrate function?
#include <iostream>
using namespace std;
typedef double (*FUNC)(double, double, double) = (line, square, cube);
double integrate(double FUNC, double a, double b){
for(int i=0; i<a && i<b; i++){
FUNC = a-b;
[code]......
C++ :: Quicksort Function To Work With Class Array
Jan 19, 2013void Quicksort(int info[],int left,int right){
int pivot = left + (right - left)/2;//it is the middle (will change sometimes but will end up in the middle
int temp;
while(left<=right){
while(info[left] < pivot){
[Code] ....
This is my quicksort function. I have tried a lot of things but I am trying to get it to work to sort all the details I have stored in an array by there age. This is how I have entered the data.
void DataEntry(Details info[],int size){
int x;
int i;
i=0;
cout << "How Many Entries Would You Like to add";
[Code] ....
I am stuck on what to do with it
C :: Delete Each Element In The List Which Is Same - Function Does Not Work Properly
Jan 18, 2014Code:
struct lista* del(struct lista* p, char* path1) {
char model[MAX2];
int len;
char ch;
printf("Type model.
[Code] ..... t
This function should delete each element in the list which is the same as this one typed by user. There are no errors, but function doesn't work. It deletes something, but not this element which should.
C++ :: Convert QT String Manipulation Function To Work With Strings?
Feb 15, 2012I have the following function I would like to convert to work with std:string. I don't understand QT strings at all.
Code:
void FromHexString(const QString &hexText, void* pData, int dataSize) {
for (int i = 0; i < hexText.length(); ++i) {
bool ok = false;
((uint8_t*)pData)[ i ] = hexText.mid( 2*i, 2 ).toInt( &ok, 16 );
}
}
C++ :: Function To Count Digits Of Entered Number Doesn't Work
Feb 19, 2013I wrote a program with function my own function which count the digits of entered number. The problem is whatever i type it shows 0 digits.Why is that?
Code:
#include <iostream>
using namespace std;
int cikCipari (int skaitlis, int cipars);
int main()
[Code] .....
C++ :: Adding Void Function In Visual Studio 2012 Does Not Work
Mar 1, 2013I am trying to add a void function in Visual Studio 2012 but it doesn't work, meanwhile in Codeblocks it does:
#include <iostream>
using namespace std;
int welcome();
int main(){
welcome();
[Code] ....
C/C++ :: Classes - Find Factorial Of Any Given Function
Aug 2, 2014I wrote this code to find the factorial of any given function ., works fine but when i put it in a class... it gives me an error ::assignment of read only variable fact;
#include <iostream>
using namespace std;
const static int fact=1;
class My_Factorial {
public:
int x;
void Get_Number(){
cout<<"enter a number to find its factorial";
[Code] ....
C++ :: How To Prevent Someone Passing Classes To Function Template
Sep 13, 2013Let say i have a following scenario:
a function like this.
Code:
template <typename T1>
print (T1 x){
cout << x << "
";
}
How do I prevent user passing a class or a structure or aanoter function to my function print. I mean i know if a wrong thing is passed that i'll get an error eventually but is there a way to explicitly check what has been passed. How is this done usually ?
C++ :: Implementing Classes And Creating A Driver Function?
Nov 30, 2012For this problem, you will design and implement 2 classes and then write a driver function to test these classes. The first will be a C++ class for an abstract data type color with a public enumeration type colorType that has the color values shown in Listing 10.8. Your abstract data type should have an attribute for storing a single value of type colortype and member functions for reading (readColor) and writing (writeColor) a color value as well as setting and accessing it. The function readColor should read a color as a string and store the corresponding color value in the value attribute of a type color object. The function writeColor should display as a string the value stored in the value attribute of a type color object (see Figure 7.5). Modify class circle and the driver function in Listing 10.9 to include and use this class. You'll need to remove the declaration for color in class circle. Test your modified driver function with the new color and circle classes.
The second class will be to design and implement a rectangle class similar to class circle. Be sure to incorporate the new color class you have written and tested in the first part of the programming exercise. Write a client program that asks the user to enter a shape name (circle or rectangle) and then asks the user for the necessary data for an object of that class. The program should create the object and display all its attributes.
The circle class .h and .cpp files as well as the original driver function will be supplied. You are to provide the .h and .cpp files for the new color class and the modified driver function as well as the .h and .cpp files for the rectangle class and the client program that uses all three classes.
What I have so far, and I'm pretty lost;
color.h
Code:
Code:
//color.h
//Color class definition
#include "stdafx.h"
#ifndef COLOR_H
#define COLOR_H
class color {
public:
enum colorType {black, blue, green, cyan, red, magenta, brown, lightgray, nocolor};
[code].....
C++ :: Defining Classes And Using Them Inside Void Main Function
May 18, 2013This is a program I developed in which we had to define a class named BOOK with the data members and member functions as shown in the program..We have to:
(i) Make the user enter the values in the array BOOK.
(ii) Display the details that the user entered.
(iii) Search for a book from the array upon its Bno and display its details.
(iv) Search for a book from the array upon its Bname and display its details.
PROGRAM:
#include<iostream.h>
#include<conio.h>
#include<stdio.h>
#include<string.h>
class BOOK {
private:
int Bno;
char Bname[20];
[Code] .....
But while running it the compiler gives the errors as:
Line 43 to 48: Illegal character '' (0x5c)
Line 69: Undefined symbol 'Display'
Line 88: 'BOOK::Bno' is not accessible.
Line 89:'BOOK::Bname' is not accessible.
Line 90:'BOOK::Author' is not accesible.
Line 91:'BOOK::Price' is not accesible.
Line 108:'BOOK::Bno' is not accessible.
Line 109:'BOOK::Bname' is not accessible.
Line 110:'BOOK::Author' is not accesible.
Line 111:'BOOK::Price' is not accesible.
from 43 to 48..the line feed was also used at many other places but there it was not given as an error so why here?
Line 69: I defined the Display() function outside the class since it contained control structures, so what's the error then?
About the lines the rest of the error( the "not accessible" ones) I know these data members are not accessible because they are in private visibility mode. But then how to make them accessible? (Without putting them in public because it was a part of the question to create the data members in private).
Visual C++ :: Implementing Classes And Creating Driver Function?
Nov 30, 2012I'm am having a few issues with this program, they stem from passing the color.h and .cpp into another .h and .cpp, and frankly getting how those two things really fit together.
For this problem, you will design and implement 2 classes and then write a driver function to test these classes. The first will be a C++ class for an abstract data type color with a public enumeration type colorType that has the color values shown in Listing 10.8. Your abstract data type should have an attribute for storing a single value of type colortype and member functions for reading (readColor) and writing (writeColor) a color value as well as setting and accessing it. The function readColor should read a color as a string and store the corresponding color value in the value attribute of a type color object. The function writeColor should display as a string the value stored in the value attribute of a type color object (see Figure 7.5). Modify class circle and the driver function in Listing 10.9 to include and use this class. You'll need to remove the declaration for color in class circle. Test your modified driver function with the new color and circle classes.
The second class will be to design and implement a rectangle class similar to class circle. Be sure to incorporate the new color class you have written and tested in the first part of the programming exercise. Write a client program that asks the user to enter a shape name (circle or rectangle) and then asks the user for the necessary data for an object of that class. The program should create the object and display all its attributes.
The circle class .h and .cpp files as well as the original driver function will be supplied. You are to provide the .h and .cpp files for the new color class and the modified driver function as well as the .h and .cpp files for the rectangle class and the client program that uses all three classes.
color.h
Code:
//color.h
//Color class definition
#include "stdafx.h"
#ifndef COLOR_H
[Code].....
C++ :: Namespaces And Friend Functions
Sep 3, 2014Are there any special considerations when using friend functions and namespaces?
objid.h
#pragma once
namespace FOO
{ typedef ULONGobjid_t;
class OBJID
{FOO::objid_tm_objnum;
[Code] ....
My C++03 compiler is giving me the following error:
C:devDATALIBOBJID.cpp(42,14) : error (346) : member "FOO::OBJID::m_objnum" is inaccessible
Is this a compiler issue, or am I missing something here trying to use a friend function? If I don't put the OBJID class in a namespace, everything compiles fine.