C++ :: Return By Reference - Statement Doesn't Return Value Of N

Jan 11, 2015

From the page: [URL] ....

#include <iostream>
using namespace std;
int n;
int& test();

[Code] ....

Explanation

In program above, the return type of function test() is int&. Hence this function returns by reference. The return statement is return n; but unlike return by value. This statement doesn't return value of n, instead it returns variable n itself.

Then the variable n is assigned to the left side of code test() = 5; and value of n is displayed.

I don't quite understand the bold sentence. Shouldn't value of n and variable n be the same?

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C++ :: Why Return Reference Doesn't Alter The Other Variable

Jun 1, 2014

Suppose i have a function:

int & f1(int & p) {
return p;
}
void main() {
int a,b;
b = 10;
a = f1(b);
a = 11;
cout<<b<<endl;
}

why when i change a, b doesnt change? a is supposed to be an alias of b right?

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C :: Will Return Root Statement At End Ever Return Value Other Than Value Passed To Function?

Mar 29, 2013

I'm writing some functions pertaining to binary trees. I've used recursion once before while learning quicksort but am still quite new and unfamiliar with it. And this is my first time touching a binary tree. So my question: In my addnode function, will the return root statement at the end ever return a value other than the value passed to the function?

Code:

#include <stdlib.h>
struct tnode
{
int data;
struct tnode * left;
struct tnode * right;
}

[code]....

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C# :: Array Doesn't Return Values

Jun 26, 2014

While working on another issue I started memory cleaning and refactoring. While refactoring I decided to create an array Resize Array Reize and Null Count:

Spoiler

public int NullCount(string[,] Original) {
try {
int returnInt =0;
for(int x =0; x<= Original.GetUpperBound(0);x++) {
if (Original[x,0]==null )
{returnInt++;}

[code]......

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C :: Void And Return Statement

Jan 11, 2014

If i declare a function as a void function. But for testing purpose if i use a return statement in the function definition. i have tested and found that the function does not return and executes the entire function. How does the function not return even if a return statement is available? Does the compiler removes this return statement or how it is?

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C++ :: Why Assignment Operator Return By Reference

Feb 1, 2015

I have code here that uses assignment operators that doesn't return by reference and it still works. So why does my book say you need to return by reference?

Here is a quote from my book:

The return type of operator= is a reference to the invoking object, so as to allow chained
assignments a=b=c.

The code below is from my book. I simply removed '&', in the original code that has assignment operators return by reference, from IntCell & operator=. This way the assignment operator no longer returns a reference, and it still works.

#include <iostream>
using namespace std;
class IntCell {
public:
explicit IntCell( int initialValue = 0 )
{ storedValue = new int{ initialValue }; }

[Code] .....

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C++ :: Return Reference For Derived Function

Jun 3, 2014

I dont know what kind of return reference I have to put to override the following derived member function in C++:

virtual SEntityPhysicalizeParams& GetPhysicsParams() override {return ???;}

The place where I should put the return value is marked with ???. SEntityPhysicalizeParams is a struct from another header from which I dont have access to it's source file.

I tried several things but noone seemed to work out and keep getting me either error "function must return a value" or "initial value of reference to non-const must be an lValue".

Here is SEntityPhysicalize where my function is refering to:

struct SEntityPhysicalizeParams
{///////////////////////////////////////////////////////////////////
SEntityPhysicalizeParams() : type(0),density(-1),mass(-1),nSlot(-1),nFlagsOR(0),nFlagsAND(UINT_MAX),
pAttachToEntity(NULL),nAttachToPart(-1),fStiffnessScale(0), bCopyJointVelocities(false),
pParticle(NULL),pBuoyancy(NULL),pPlayerDimensions(NULL),pPlayerDynamics(NULL),
pCar(NULL),pAreaDef(NULL),nLod(0),szPropsOverride(0) {};

[Code] ....

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C :: Returning Structure From A Function Using By Return Statement

Jul 14, 2014

I'm beginners in C Programming, i have a question about Structure in C. i know in Function it is possible for

1. Sending the value of argument
2. Sending the address of the argument
3. Returning values from a function by return statement

Does in Structure it is possible for

1. returning structure from a function using by return statement

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C/C++ :: Updating Value Passed Through Functions With No Return Statement?

Sep 13, 2014

I am supposed to update the value temp without using a return statement, or a global variable. I have never ran across a problem like this before and I am totally stuck. I think I'm missing something really simple and need a hint. Here is the code that was provided for "fixing".

#include "stdafx.h"
#include <iostream>
#include <cstdlib>
using namespace std;

[Code]....

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C++ :: Find Function - Return Reference To A Vector

Oct 12, 2014

Okay, so for an assignment I need to write a function called find() that returns a reference to a vector. So I have vector <int> & find(string & key); If I do this, I get the obvious warning warning: reference to local variable 'lineNum' returned [enabled by default].

If I do vector<int> & find(string & key) const; I get a huge error that starts out like

In member function 'std::vector<int>& index_table::find(std::string&) const':
indextable.cpp:74:30: error: no match for 'operator='

Am I using the const identifier incorrectly?

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C/C++ :: Difference Between Return 0 And Return -1

Oct 17, 2013

difference between return 0 and return -1 .and exit(0) and exit(1)

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C++ :: Do While Statement Doesn't Work

Nov 21, 2013

#include <iostream>
#include <string>
using namespace std ;
int main() {
string bored ;
do {
cout << " program" <<endl ;

[Code] .....

I made this as a simple do/while program, and if i run it, the second do/while statement will keep on going forever, without the [cin >> bored;] line working?

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C++ :: Functions Does Not Return New Value

Jul 24, 2014

In my program below, in the getage and get level functions, if an incorrect input is entered, then the correct one is entered after, it still returns the bad input back to main.

#include "stdafx.h"
#include <cstdlib>
#include <iostream>
#include <string>
#include <cstring>
#include <cmath>

[Code] ....

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C++ :: How To Return Value From A Pointer

Apr 1, 2013

Here is what's up:

struct Square {int number, myClass* myclass};
int main() {
vector<myClass> classes;
myClass unrelated;
classes.push_back(unrelated);
Square newClass = {3, &classes.at(0)};
.
.
.

myClass is a class I have. Now, in the class, I have a function what_value and I need to get the classes.at(0) from the pointer to it in another function. But the problem is, how can I do it? I'm completely stumped, here's what I thought of:

newClass.*myclass.what_value();

And it I get an error from the compiler. Basically, how can I do this in another function with a pointer:

classes.at(0).what_value();

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C++ :: Use EOF And Carriage Return Together?

Jun 9, 2013

I'm going to write a program that takes string until end of file(eof). An condition must be considered and that is it must also terminate by a new line. For example when it's prompting me to enter a string if I press enter it must terminate and exit the program. How is it possible? I tried saving carriage return("") as a string then I compared it with the entered string but it didn't work.

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C++ :: More Than 1 Return Value Per Sub Program?

Nov 11, 2014

Is it possible to have more than 1 return value from a subprogram?

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C++ :: Function Will Not Return Value

Jan 14, 2015

Why my function will not return this int. It does make it into the if(... prints "test 32" but will not return the given value(123456789).

#include <iostream>
using namespace std;
int lastZero(int x[]);
int main(){
int myArray[] = {1,1,1};
lastZero(myArray);

[Code] ...

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C/C++ :: Why Write Return 0 At The End

Jan 22, 2013

#include <iostream.h>
#include <conio.h>
int main ()
{
cout << "Hello World";
getch();
return 0;
}

In the above code, why is it necessary to write getch() and return 0? What is their purpose?

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C++ :: How To Return Another Object Value

Nov 8, 2014

How can I return other object's value in a function(see code and comments)?

Person.h

Code:
#include <iostream>
#include <string>
using namespace std;
class Person{
public:
Person();
Person(string pname, int page);

[Code] ....

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C++ :: Return A Node Using Recursion

Mar 27, 2013

So the task is to find the node with minimum value of a binary tree (not binary search tree). the input is the pointer to the root of the tree. and i cannot make recursion work when i do if conditions. here is what i have Code: /*function 3-takses as input the pointer to the root of the tree and returns a pointer to the node with the minimum value*/

CPPtr minimumvalue(CPPtr SP){
CPPtr min = NULL; //node of minimum value
if(SP== NULL){ // if there is a node, begin comparing
return NULL;
}
else{
if(SP->data<SP->left->data){ //if the node has smaller value than its left child
min = SP; //update node of minimum value

[code].....

no matter where i call my function i get errors like unhandled exception at some memory. how to use recursion in this?

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C++ :: Return Value For A Type Class?

Apr 25, 2014

Code:
returnType operatorOperatorSymbol (parameterList); // syntax for operator overloading
Class Fraction

public:
Fraction operator-(const Fraction& f1){
Fraction r;
return r;
}

Is this even syntactically correct? It gives me errors. Im just trying to compile it without errors. I think the function makes sense since its returning a type Class

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C++ :: Best Way To Return Values From A Function?

Jan 24, 2014

I wanted to return a string I can do

Code:

string parseFilename(string fileName){
return fileName.subtr(/*blah*/);
}

Can I also use pointers/references here though? When would you use a pointer and when just a return statement?

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C :: Function Return Code / Value?

Sep 27, 2014

I have a function that needs to return a "uint8_t" value. However before doing the processing I need to perform a test on the argument to check if it's between expected boundaries. Although this function works it gives (a logical) warning that not always a value is returned although expected. What is the normal way for functions like these where I normally should return e.g. -1 in case the test doesn't succeed and otherwise the uint8_t (t) value?

Code:
uint8_t myFunc(int a) {
if (a >= 0 && a <= 100) {
// Perform actions
uint8_t = ...
return t;
}
}

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C :: Functions With Different Return Type?

Feb 26, 2015

understand the below program.

Why I'm getting output y is 6.000000

Code:
#include <stdio.h>
int square(double a);
int main()

[Code].....

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C :: How To Return Two Values With A Pointer

Mar 6, 2015

Here is the part of my code that I need to return two values. I am working on a roulette program and I need to return the choice and the number they are betting on. How can I use a pointer to achieve this?

Code:
int makeBet(char choice, int num){

printf("
What type of bet would you like to place? ");
printf("
Type n for number.
Type e for even/odd.
Type d for dozen.

[Code] ....