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<!DOCTYPE html>

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content="A C++ function can return a reference in a similar way as it returns a pointer. When returning a reference, be careful that the object being referred to does not go out of scope. So it is not legal to return a reference to local var. But you can always return a reference on a static variable." />

content="c++ return by reference, cpp return by reference, return by reference in c++, return by reference in cpp, what is return by reference, what is return by reference in c++, what is return by reference in cpp, return by reference, return by reference in function, return by reference in function in c++, return by reference in funtion in cpp, return by reference with example in c++, return by reference with example in cpp" />

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<h3 class="pb-3 pt-3">C++ Return by Reference</h3>

<p>In this tutorial, we are going to learn about returning a value by reference, we will also see how to use

them in C++ programming.</p>

<p>Apart from passing values by reference, you can also return a value by reference.</p>

<p>But before moving ahead it is important that you must know concept of <strong>Global variables</strong>.

</p>

<p>A <strong>Global variables</strong> in the program is a variable defined outside the function. It has a

global scope means it holds its value throughout the lifetime of the program. Hence, it can be accessed

throughout the program by any function defined within the program.</p>

<pre>#include <iostream>

using namespace std;

int c = 12; // Global variable

void test_func();

int main() {

... .. ...

return 0;

}

void test_func() {

... .. ...

}</pre>

<p>In the above example <code>c</code> is a global variable, hence it can be accessed

by both the functions, i.e. <code>test_func()</code> and <code>main()</code></p>

<p>Now back to the topic, let’s see an example of Return a value by

Reference in C++.</p>

<hr />

<p><strong>Example 1:</strong></p>

<pre>#include <iostream>

using namespace std;

int number; // Global variable

int& test_func(); // Function declaration

int main() {

test_func() = 10;

cout << number;

return 0;

}

int& test_func() {

return number;

}</pre>

<p><strong>Output :</strong></p>

<p><strong># </strong>Explanation :</p>

</div>

<p>In the above program, you can see the return type of the function

<code>test_func()</code> is <code>int&</code>. We use this return type when we have to return

a value by reference.</p>

<p>The function <code>test_func()</code> returns the reference of the variable

<code>number</code>.</p>

<p>In other words, <code>return number</code>, doesn’t return value of number,

instead it return its reference (address).</p>

<p>On this returned address the value can be assigned in <code>main()</code>, like in

our case it is <code>test_func() = 10</code> .</p>

<p>And hence the value got displayed on screen by <code>cout << number</code>.</p>

<hr />

<h4 class="pt-3 pb-3">Points to ponder :-</h4>

<ul>

<li>

You cannot return a constant value from a function declared

for returning reference. This can only be done in ordinary

functions.

</li>

<li>

You can't return a local variable by reference.

</li>

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