Reference declaration in C++ - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a reference to an integer variable.

C++

int x = 10;
int [1] y = x;

Drag options to blanks, or click blank then click option'

A&

B*

C#

D%

Attempts:

3 left

💡 Hint

Common Mistakes

Using '*' which declares a pointer instead of a reference.

Using '#' or '%' which are not valid for references.

The symbol & is used in C++ to declare a reference variable.

2fill in blank

medium

Complete the code to declare a reference to a double variable.

C++

double pi = 3.14;
double [1] refPi = pi;

Drag options to blanks, or click blank then click option'

A*

B^

C&

D&&

Attempts:

3 left

💡 Hint

Common Mistakes

Using '*' which declares a pointer.

Using '&&' which is for rvalue references.

Use & to declare a reference variable in C++.

3fill in blank

hard

Fix the error in the reference declaration.

C++

int a = 5;
int [1] refA = &a;

Drag options to blanks, or click blank then click option'

A#

B*

C&&

D&

Attempts:

3 left

💡 Hint

Common Mistakes

Using '*' which declares a pointer.

Initializing a reference with an address using '&a' instead of 'a'.

References are declared with & and initialized with the variable itself, not its address. The code should be int &refA = a;.

4fill in blank

hard

Fill both blanks to declare a reference and initialize it correctly.

C++

float value = 9.8f;
float [1] refValue = [2];

Drag options to blanks, or click blank then click option'

A&

Bvalue

CrefValue

D*value

Attempts:

3 left

💡 Hint

Common Mistakes

Using '*value' which is invalid syntax.

Using the reference variable name to initialize itself.

Use & to declare a reference and initialize it with the variable name.

5fill in blank

hard

Fill all three blanks to declare a constant reference to an integer.

C++

const int num = 100;
const int [1] [2] = [3];

Drag options to blanks, or click blank then click option'

A&

BrefNum

Cnum

D*

Attempts:

3 left

💡 Hint

Common Mistakes

Using '*' instead of '&' for reference.

Initializing with the reference variable name instead of the original variable.

To declare a constant reference, use const int &refNum = num;.